641973976992 has 72 divisors (see below), whose sum is σ = 1825727589504. Its totient is φ = 213977952384.

The previous prime is 641973976979. The next prime is 641973977041. The reversal of 641973976992 is 299679379146.

641973976992 is a `hidden beast` number, since 6 + 4 + 1 + 97 + 397 + 69 + 92 = 666.

641973976992 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (72).

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a self number, because there is not a number n which added to its sum of digits gives 641973976992.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5251153 + ... + 5372015.

It is an arithmetic number, because the mean of its divisors is an integer number (25357327632).

Almost surely, 2^641973976992 is an apocalyptic number.

It is an amenable number.

641973976992 is an abundant number, since it is smaller than the sum of its proper divisors (1183753612512).

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

641973976992 is a wasteful number, since it uses less digits than its factorization.

641973976992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 139322 (or 139311 counting only the distinct ones).

The product of its digits is 277766496, while the sum is 72.

The spelling of 641973976992 in words is "six hundred forty-one billion, nine hundred seventy-three million, nine hundred seventy-six thousand, nine hundred ninety-two".