20649764 has 24 divisors (see below), whose sum is σ = 38918880. Its totient is φ = 9550976.

The previous prime is 20649757. The next prime is 20649767. The reversal of 20649764 is 46794602.

It is not an unprimeable number, because it can be changed into a prime (20649767) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1439 + ... + 6585.

It is an arithmetic number, because the mean of its divisors is an integer number (1621620).

Almost surely, 2^20649764 is an apocalyptic number.

It is an amenable number.

20649764 is a deficient number, since it is larger than the sum of its proper divisors (18269116).

20649764 is a wasteful number, since it uses less digits than its factorization.

20649764 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5227 (or 5225 counting only the distinct ones).

The product of its (nonzero) digits is 72576, while the sum is 38.

The square root of 20649764 is about 4544.2011399145. The cubic root of 20649764 is about 274.3500419042.

The spelling of 20649764 in words is "twenty million, six hundred forty-nine thousand, seven hundred sixty-four".