256274399 has 2 divisors, whose sum is σ = 256274400. Its totient is φ = 256274398.

The previous prime is 256274393. The next prime is 256274401. The reversal of 256274399 is 993472652.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 256274399 - 2⁸ = 256274143 is a prime.

It is a super-2 number, since 2×256274399² = 131353135165622402, which contains 22 as substring.

Together with 256274401, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (256274393) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128137199 + 128137200.

It is an arithmetic number, because the mean of its divisors is an integer number (128137200).

Almost surely, 2^256274399 is an apocalyptic number.

256274399 is a deficient number, since it is larger than the sum of its proper divisors (1).

256274399 is an equidigital number, since it uses as much as digits as its factorization.

256274399 is an evil number, because the sum of its binary digits is even.

The product of its digits is 816480, while the sum is 47.

The square root of 256274399 is about 16008.5726721654. The cubic root of 256274399 is about 635.1872050190.

The spelling of 256274399 in words is "two hundred fifty-six million, two hundred seventy-four thousand, three hundred ninety-nine".