64563660 has 72 divisors (see below), whose sum is σ = 223825056. Its totient is φ = 14757120.

The previous prime is 64563647. The next prime is 64563677. The reversal of 64563660 is 6636546.

64563660 is a `hidden beast` number, since 645 + 6 + 3 + 6 + 6 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 24361 + ... + 26880.

Almost surely, 2^64563660 is an apocalyptic number.

64563660 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

64563660 is an abundant number, since it is smaller than the sum of its proper divisors (159261396).

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

64563660 is a wasteful number, since it uses less digits than its factorization.

64563660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51263 (or 51258 counting only the distinct ones).

The product of its (nonzero) digits is 77760, while the sum is 36.

The square root of 64563660 is about 8035.1515231513. The cubic root of 64563660 is about 401.1708610337.

The spelling of 64563660 in words is "sixty-four million, five hundred sixty-three thousand, six hundred sixty".