20388764 has 24 divisors (see below), whose sum is σ = 40618368. Its totient is φ = 8864240.

The previous prime is 20388761. The next prime is 20388773. The reversal of 20388764 is 46788302.

20388764 = T₁₃₂₀ + T₁₃₂₁ + ... + T₁₃₄₂.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20388761) 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, 9062 + ... + 11085.

It is an arithmetic number, because the mean of its divisors is an integer number (1692432).

Almost surely, 2^20388764 is an apocalyptic number.

It is an amenable number.

20388764 is a deficient number, since it is larger than the sum of its proper divisors (20229604).

20388764 is a wasteful number, since it uses less digits than its factorization.

20388764 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20185 (or 20183 counting only the distinct ones).

The product of its (nonzero) digits is 64512, while the sum is 38.

The square root of 20388764 is about 4515.3918988278. The cubic root of 20388764 is about 273.1892670638.

The spelling of 20388764 in words is "twenty million, three hundred eighty-eight thousand, seven hundred sixty-four".