20646764 has 12 divisors (see below), whose sum is σ = 36228864. Its totient is φ = 10295664.

The previous prime is 20646763. The next prime is 20646797. The reversal of 20646764 is 46764602.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (20646763) 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 3 ways as a sum of consecutive naturals, for example, 5207 + ... + 8270.

It is an arithmetic number, because the mean of its divisors is an integer number (3019072).

Almost surely, 2^20646764 is an apocalyptic number.

It is an amenable number.

20646764 is a deficient number, since it is larger than the sum of its proper divisors (15582100).

20646764 is a wasteful number, since it uses less digits than its factorization.

20646764 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13864 (or 13862 counting only the distinct ones).

The product of its (nonzero) digits is 48384, while the sum is 35.

The square root of 20646764 is about 4543.8710369023. The cubic root of 20646764 is about 274.3367553926.

The spelling of 20646764 in words is "twenty million, six hundred forty-six thousand, seven hundred sixty-four".