256603431 has 16 divisors (see below), whose sum is σ = 392729600. Its totient is φ = 145987488.

The previous prime is 256603421. The next prime is 256603439. The reversal of 256603431 is 134306652.

It is not a de Polignac number, because 256603431 - 2¹⁸ = 256341287 is a prime.

It is a super-2 number, since 2×256603431² = 131690641601943522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256603439) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 21871 + ... + 31488.

It is an arithmetic number, because the mean of its divisors is an integer number (24545600).

Almost surely, 2^256603431 is an apocalyptic number.

256603431 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

256603431 is a deficient number, since it is larger than the sum of its proper divisors (136126169).

256603431 is a wasteful number, since it uses less digits than its factorization.

256603431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53598.

The product of its (nonzero) digits is 12960, while the sum is 30.

The square root of 256603431 is about 16018.8461194931. The cubic root of 256603431 is about 635.4589287871.

The spelling of 256603431 in words is "two hundred fifty-six million, six hundred three thousand, four hundred thirty-one".