256616311281 has 48 divisors (see below), whose sum is σ = 380205427392. Its totient is φ = 153826928640.

The previous prime is 256616311241. The next prime is 256616311319. The reversal of 256616311281 is 182113616652.

It is not a de Polignac number, because 256616311281 - 2¹⁰ = 256616310257 is a prime.

It is a super-2 number, since 2×256616311281² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (256616311241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 26135085 + ... + 26144901.

It is an arithmetic number, because the mean of its divisors is an integer number (7920946404).

Almost surely, 2^256616311281 is an apocalyptic number.

It is an amenable number.

256616311281 is a deficient number, since it is larger than the sum of its proper divisors (123589116111).

256616311281 is a wasteful number, since it uses less digits than its factorization.

256616311281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10622 (or 10611 counting only the distinct ones).

The product of its digits is 103680, while the sum is 42.

The spelling of 256616311281 in words is "two hundred fifty-six billion, six hundred sixteen million, three hundred eleven thousand, two hundred eighty-one".