664042536 has 40 divisors (see below), whose sum is σ = 1859935770. Its totient is φ = 221347296.

The previous prime is 664042517. The next prime is 664042543. The reversal of 664042536 is 635240466.

664042536 is a `hidden beast` number, since 6 + 640 + 4 + 2 + 5 + 3 + 6 = 666.

It can be written as a sum of positive squares in only one way, i.e., 577440900 + 86601636 = 24030^2 + 9306^2 .

It is a super-2 number, since 2×664042536² = 881904979234622592, which contains 22 as substring.

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

It is a self number, because there is not a number n which added to its sum of digits gives 664042536.

It is an unprimeable number.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 511731 + ... + 513026.

Almost surely, 2^664042536 is an apocalyptic number.

It is an amenable number.

664042536 is an abundant number, since it is smaller than the sum of its proper divisors (1195893234).

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

664042536 is a wasteful number, since it uses less digits than its factorization.

664042536 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1024775 (or 1024762 counting only the distinct ones).

The product of its (nonzero) digits is 103680, while the sum is 36.

The square root of 664042536 is about 25769.0227987015. The cubic root of 664042536 is about 872.4327629131.

The spelling of 664042536 in words is "six hundred sixty-four million, forty-two thousand, five hundred thirty-six".