256621061364531 has 8 divisors (see below), whose sum is σ = 347268301946304. Its totient is φ = 168527264179560.

The previous prime is 256621061364523. The next prime is 256621061364587. The reversal of 256621061364531 is 135463160126652.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 256621061364531 - 2³ = 256621061364523 is a prime.

It is a super-2 number, since 2×256621061364531² (a number of 30 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (256621061364931) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 638360848965 + ... + 638360849366.

It is an arithmetic number, because the mean of its divisors is an integer number (43408537743288).

Almost surely, 2^{256621061364531} is an apocalyptic number.

256621061364531 is a deficient number, since it is larger than the sum of its proper divisors (90647240581773).

256621061364531 is a wasteful number, since it uses less digits than its factorization.

256621061364531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1276721698401.

The product of its (nonzero) digits is 4665600, while the sum is 51.

The spelling of 256621061364531 in words is "two hundred fifty-six trillion, six hundred twenty-one billion, sixty-one million, three hundred sixty-four thousand, five hundred thirty-one".