20655656660 has 24 divisors (see below), whose sum is σ = 43643001696. Its totient is φ = 8211572640.

The previous prime is 20655656657. The next prime is 20655656677. The reversal of 20655656660 is 6665655602.

It is a Smith number, since the sum of its digits (47) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3164786 + ... + 3171305.

It is an arithmetic number, because the mean of its divisors is an integer number (1818458404).

Almost surely, 2^20655656660 is an apocalyptic number.

20655656660 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20655656660 is an abundant number, since it is smaller than the sum of its proper divisors (22987345036).

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

20655656660 is a wasteful number, since it uses less digits than its factorization.

20655656660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6336263 (or 6336261 counting only the distinct ones).

The product of its (nonzero) digits is 1944000, while the sum is 47.

The spelling of 20655656660 in words is "twenty billion, six hundred fifty-five million, six hundred fifty-six thousand, six hundred sixty".