20647888920 has 48 divisors (see below), whose sum is σ = 67105640160. Its totient is φ = 5506103616.

The previous prime is 20647888913. The next prime is 20647888939. The reversal of 20647888920 is 2988874602.

20647888920 is a `hidden beast` number, since 2 + 0 + 6 + 478 + 88 + 92 + 0 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 28677264 + ... + 28677983.

It is an arithmetic number, because the mean of its divisors is an integer number (1398034170).

Almost surely, 2^20647888920 is an apocalyptic number.

20647888920 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20647888920 is an abundant number, since it is smaller than the sum of its proper divisors (46457751240).

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

20647888920 is a wasteful number, since it uses less digits than its factorization.

20647888920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57355264 (or 57355257 counting only the distinct ones).

The product of its (nonzero) digits is 3096576, while the sum is 54.

The spelling of 20647888920 in words is "twenty billion, six hundred forty-seven million, eight hundred eighty-eight thousand, nine hundred twenty".