646976394160 has 20 divisors (see below), whose sum is σ = 1504220116608. Its totient is φ = 258790557632.

The previous prime is 646976394131. The next prime is 646976394193. The reversal of 646976394160 is 61493679646.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (20).

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, 4043602384 + ... + 4043602543.

Almost surely, 2^646976394160 is an apocalyptic number.

It is an amenable number.

646976394160 is an abundant number, since it is smaller than the sum of its proper divisors (857243722448).

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

646976394160 is a wasteful number, since it uses less digits than its factorization.

646976394160 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8087204940 (or 8087204934 counting only the distinct ones).

The product of its (nonzero) digits is 35271936, while the sum is 61.

The spelling of 646976394160 in words is "six hundred forty-six billion, nine hundred seventy-six million, three hundred ninety-four thousand, one hundred sixty".