256616531 has 2 divisors, whose sum is σ = 256616532. Its totient is φ = 256616530.

The previous prime is 256616519. The next prime is 256616537. The reversal of 256616531 is 135616652.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 256616531 - 2¹⁴ = 256600147 is a prime.

It is a super-2 number, since 2×256616531² = 131704087964947922, which contains 22 as substring.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 256616491 and 256616500.

It is not a weakly prime, because it can be changed into another prime (256616537) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128308265 + 128308266.

It is an arithmetic number, because the mean of its divisors is an integer number (128308266).

Almost surely, 2^256616531 is an apocalyptic number.

256616531 is a deficient number, since it is larger than the sum of its proper divisors (1).

256616531 is an equidigital number, since it uses as much as digits as its factorization.

256616531 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 32400, while the sum is 35.

The square root of 256616531 is about 16019.2550076463. The cubic root of 256616531 is about 635.4697423218.

The spelling of 256616531 in words is "two hundred fifty-six million, six hundred sixteen thousand, five hundred thirty-one".