64637668 has 12 divisors (see below), whose sum is σ = 116173372. Its totient is φ = 31445280.

The previous prime is 64637663. The next prime is 64637669. The reversal of 64637668 is 86673646.

It can be written as a sum of positive squares in 2 ways, for example, as 58644964 + 5992704 = 7658^2 + 2448^2 .

It is not an unprimeable number, because it can be changed into a prime (64637663) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 218223 + ... + 218518.

Almost surely, 2^64637668 is an apocalyptic number.

It is an amenable number.

64637668 is a deficient number, since it is larger than the sum of its proper divisors (51535704).

64637668 is a wasteful number, since it uses less digits than its factorization.

64637668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 436782 (or 436780 counting only the distinct ones).

The product of its digits is 870912, while the sum is 46.

The square root of 64637668 is about 8039.7554689182. The cubic root of 64637668 is about 401.3240871468.

The spelling of 64637668 in words is "sixty-four million, six hundred thirty-seven thousand, six hundred sixty-eight".