20666764 has 24 divisors (see below), whose sum is σ = 38456208. Its totient is φ = 9684480.

The previous prime is 20666759. The next prime is 20666783. The reversal of 20666764 is 46766602.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20799 + ... + 21769.

It is an arithmetic number, because the mean of its divisors is an integer number (1602342).

Almost surely, 2^20666764 is an apocalyptic number.

It is an amenable number.

20666764 is a deficient number, since it is larger than the sum of its proper divisors (17789444).

20666764 is a wasteful number, since it uses less digits than its factorization.

20666764 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1305 (or 1303 counting only the distinct ones).

The product of its (nonzero) digits is 72576, while the sum is 37.

The square root of 20666764 is about 4546.0712708887. The cubic root of 20666764 is about 274.4253078398.

The spelling of 20666764 in words is "twenty million, six hundred sixty-six thousand, seven hundred sixty-four".