401

401
Basic Information
Cardinal Number	four hundred and one
Ordinal Number	four hundred and first
Roman Numeral	CDI
Greek Numeral	ΥΑ´
Factorization	401
Different Representations
Binary Form	1100100012
Ternary Form	1122123
Quaternary Form	121014
Quinary Form	31015
Senary Form	15056
Septenary Form	11127
Octal Form	6218
Nonary Form	4859
Undecimal Form	33511
Duodecimal Form	29512
Tridecimal Form	24B13
Quattuordecimal Form	20914
Quindecimal Form	1BB15
Hexadecimal Form	19116
Septendecimal Form	16A17
Octodecimal Form	14518
Novemdecimal Form	12219
Vigesimal Form	10120
Unvigesimal Form	J221
Duovigesimal Form	I522
Trevigesimal Form	HA23
Quattuorvigesimal Form	GH24
Quinvigesimal Form	G125
Hexavigesimal Form	FB26
Septenvigesimal Form	EN27
Octovigesimal Form	E928
Novemvigesimal Form	DO29
Trigesimal Form	DB30
Untrigesimal Form	CT31
Duotrigesimal Form	CH32
Tretrigesimal Form	C533
Quattuortrigesimal Form	BR34
Quintrigesimal Form	BG35
Hexatrigesimal Form	B536
Previous	397
Current	401
Next	409

 401 is a prime number from 401-500. 401 has 2 factors, 1 and 401. It is the 79th prime number, and the first prime number from 401-500.

Proofs

• — 401 is divisible by 1.

• — 401 is not divisible by 2-400.

• — 401 is divisible by 401.

Relationship with other odd numbers

The numbers before

• The previous prime number is 397.
  • 397 and 401 are four numbers apart; therefore, they are cousin primes.
• The previous prime number before 397 is 389.
  • In particular, 391 is not a prime number, because it is the product of 17 and 23.

The numbers after

• The next prime number is 409.
  • 403 is divisible by 13 and 31, while 407 is divisible by 11 and 37.
• 419 is the next prime number after 409.
  • 413 is the product of 7 and 59.

Trivia

• It is the sum of seven consecutive prime (43+47+53+59+61+67+71), and also nine consecutive primes (29+31+37+41+43+47+53+59+61)
• This, 431, and 461 are the three primes in the 400s where the number n887 is prime.

Prime Numbers 1-1,000