643578036256 has 24 divisors (see below), whose sum is σ = 1333730800080. Its totient is φ = 304852753728.

The previous prime is 643578036173. The next prime is 643578036263. The reversal of 643578036256 is 652630875346.

It is a super-2 number, since 2×643578036256² (a number of 24 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 643578036197 and 643578036206.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 529257646 + ... + 529258861.

It is an arithmetic number, because the mean of its divisors is an integer number (55572116670).

Almost surely, 2^643578036256 is an apocalyptic number.

It is an amenable number.

643578036256 is an abundant number, since it is smaller than the sum of its proper divisors (690152763824).

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

643578036256 is a wasteful number, since it uses less digits than its factorization.

643578036256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1058516536 (or 1058516528 counting only the distinct ones).

The product of its (nonzero) digits is 21772800, while the sum is 55.

The spelling of 643578036256 in words is "six hundred forty-three billion, five hundred seventy-eight million, thirty-six thousand, two hundred fifty-six".