640912685952 has 128 divisors (see below), whose sum is σ = 2122503148800. Its totient is φ = 166470819840.

The previous prime is 640912685921. The next prime is 640912686023. The reversal of 640912685952 is 259586219046.

It is a tau number, because it is divible by the number of its divisors (128).

It is a junction number, because it is equal to n+sod(n) for n = 640912685892 and 640912685901.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10808377 + ... + 10867512.

It is an arithmetic number, because the mean of its divisors is an integer number (16582055850).

Almost surely, 2^640912685952 is an apocalyptic number.

It is an amenable number.

640912685952 is an abundant number, since it is smaller than the sum of its proper divisors (1481590462848).

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

640912685952 is a wasteful number, since it uses less digits than its factorization.

640912685952 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21675924 (or 21675912 counting only the distinct ones).

The product of its (nonzero) digits is 9331200, while the sum is 57.

The spelling of 640912685952 in words is "six hundred forty billion, nine hundred twelve million, six hundred eighty-five thousand, nine hundred fifty-two".