66390966 has 24 divisors (see below), whose sum is σ = 144008904. Its totient is φ = 22105440.

The previous prime is 66390943. The next prime is 66390983. The reversal of 66390966 is 66909366.

66390966 is a `hidden beast` number, since 6 + 639 + 0 + 9 + 6 + 6 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 21810 + ... + 24666.

It is an arithmetic number, because the mean of its divisors is an integer number (6000371).

Almost surely, 2^66390966 is an apocalyptic number.

66390966 is an abundant number, since it is smaller than the sum of its proper divisors (77617938).

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

66390966 is a wasteful number, since it uses less digits than its factorization.

66390966 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4156 (or 4153 counting only the distinct ones).

The product of its (nonzero) digits is 314928, while the sum is 45.

The square root of 66390966 is about 8148.0651691061. The cubic root of 66390966 is about 404.9204050257.

Subtracting 66390966 from its reverse (66909366), we obtain a square (518400 = 720²).

The spelling of 66390966 in words is "sixty-six million, three hundred ninety thousand, nine hundred sixty-six".