20664684 has 36 divisors (see below), whose sum is σ = 52752336. Its totient is φ = 6820128.

The previous prime is 20664667. The next prime is 20664689. The reversal of 20664684 is 48646602.

It is a happy number.

20664684 is a `hidden beast` number, since 2 + 0 + 6 + 646 + 8 + 4 = 666.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (20664689) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 922 + ... + 6494.

Almost surely, 2^20664684 is an apocalyptic number.

It is an amenable number.

20664684 is an abundant number, since it is smaller than the sum of its proper divisors (32087652).

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

20664684 is a wasteful number, since it uses less digits than its factorization.

20664684 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5686 (or 5681 counting only the distinct ones).

The product of its (nonzero) digits is 55296, while the sum is 36.

The square root of 20664684 is about 4545.8424961716. The cubic root of 20664684 is about 274.4161010479.

The spelling of 20664684 in words is "twenty million, six hundred sixty-four thousand, six hundred eighty-four".