65538666 has 32 divisors (see below), whose sum is σ = 150667200. Its totient is φ = 21092400.

The previous prime is 65538659. The next prime is 65538679. The reversal of 65538666 is 66683556.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19360 + ... + 22491.

It is an arithmetic number, because the mean of its divisors is an integer number (4708350).

Almost surely, 2^65538666 is an apocalyptic number.

65538666 is an abundant number, since it is smaller than the sum of its proper divisors (85128534).

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

65538666 is a wasteful number, since it uses less digits than its factorization.

65538666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41891 (or 41885 counting only the distinct ones).

The product of its digits is 777600, while the sum is 45.

The square root of 65538666 is about 8095.5954691425. The cubic root of 65538666 is about 403.1802029325.

The spelling of 65538666 in words is "sixty-five million, five hundred thirty-eight thousand, six hundred sixty-six".