256421626 has 16 divisors (see below), whose sum is σ = 395734248. Its totient is φ = 124537600.

The previous prime is 256421623. The next prime is 256421681. The reversal of 256421626 is 626124652.

It can be written as a sum of positive squares in 4 ways, for example, as 183575401 + 72846225 = 13549^2 + 8535^2 .

It is a junction number, because it is equal to n+sod(n) for n = 256421591 and 256421600.

It is not an unprimeable number, because it can be changed into a prime (256421621) 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 7 ways as a sum of consecutive naturals, for example, 12396 + ... + 25816.

Almost surely, 2^256421626 is an apocalyptic number.

256421626 is a deficient number, since it is larger than the sum of its proper divisors (139312622).

256421626 is a wasteful number, since it uses less digits than its factorization.

256421626 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13697.

The product of its digits is 34560, while the sum is 34.

The square root of 256421626 is about 16013.1703918993. The cubic root of 256421626 is about 635.3088179003.

The spelling of 256421626 in words is "two hundred fifty-six million, four hundred twenty-one thousand, six hundred twenty-six".