664400560 has 40 divisors (see below), whose sum is σ = 1556547696. Its totient is φ = 263727360.

The previous prime is 664400549. The next prime is 664400629. The reversal of 664400560 is 65004466.

It is a tau number, because it is divible by the number of its divisors (40).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21219 + ... + 42178.

Almost surely, 2^664400560 is an apocalyptic number.

It is an amenable number.

664400560 is an abundant number, since it is smaller than the sum of its proper divisors (892147136).

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

664400560 is a wasteful number, since it uses less digits than its factorization.

664400560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63541 (or 63535 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 31.

The square root of 664400560 is about 25775.9686529915. The cubic root of 664400560 is about 872.5895278449.

The spelling of 664400560 in words is "six hundred sixty-four million, four hundred thousand, five hundred sixty".