20656764 has 36 divisors (see below), whose sum is σ = 52579800. Its totient is φ = 6837600.

The previous prime is 20656763. The next prime is 20656771. The reversal of 20656764 is 46765602.

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

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20656763) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3439 + ... + 7289.

It is an arithmetic number, because the mean of its divisors is an integer number (1460550).

Almost surely, 2^20656764 is an apocalyptic number.

It is an amenable number.

20656764 is an abundant number, since it is smaller than the sum of its proper divisors (31923036).

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

20656764 is a wasteful number, since it uses less digits than its factorization.

20656764 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4010 (or 4005 counting only the distinct ones).

The product of its (nonzero) digits is 60480, while the sum is 36.

The square root of 20656764 is about 4544.9712870380. The cubic root of 20656764 is about 274.3810387610.

The spelling of 20656764 in words is "twenty million, six hundred fifty-six thousand, seven hundred sixty-four".