256511032464 has 320 divisors, whose sum is σ = 741902515200. Its totient is φ = 76025972736.

The previous prime is 256511032457. The next prime is 256511032513. The reversal of 256511032464 is 464230115652.

It is a super-2 number, since 2×256511032464² (a number of 24 digits) contains 22 as substring.

It is an unprimeable number.

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 63 ways as a sum of consecutive naturals, for example, 321845314 + ... + 321846110.

It is an arithmetic number, because the mean of its divisors is an integer number (2318445360).

Almost surely, 2^256511032464 is an apocalyptic number.

256511032464 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 256511032464, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (370951257600).

256511032464 is an abundant number, since it is smaller than the sum of its proper divisors (485391482736).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

256511032464 is a wasteful number, since it uses less digits than its factorization.

256511032464 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1182 (or 1176 counting only the distinct ones).

The product of its (nonzero) digits is 172800, while the sum is 39.

The spelling of 256511032464 in words is "two hundred fifty-six billion, five hundred eleven million, thirty-two thousand, four hundred sixty-four".