66813964 has 24 divisors (see below), whose sum is σ = 134597120. Its totient is φ = 28426896.

The previous prime is 66813953. The next prime is 66813977. The reversal of 66813964 is 46931866.

It is a self number, because there is not a number n which added to its sum of digits gives 66813964.

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, 4692 + ... + 12475.

Almost surely, 2^66813964 is an apocalyptic number.

It is an amenable number.

66813964 is an abundant number, since it is smaller than the sum of its proper divisors (67783156).

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

66813964 is a wasteful number, since it uses less digits than its factorization.

66813964 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17317 (or 17315 counting only the distinct ones).

The product of its digits is 186624, while the sum is 43.

The square root of 66813964 is about 8173.9809150744. The cubic root of 66813964 is about 405.7785440818.

The spelling of 66813964 in words is "sixty-six million, eight hundred thirteen thousand, nine hundred sixty-four".