20663655408 has 60 divisors (see below), whose sum is σ = 63086770968. Its totient is φ = 6261713280.

The previous prime is 20663655407. The next prime is 20663655433. The reversal of 20663655408 is 80455636602.

20663655408 is a `hidden beast` number, since 2 + 0 + 6 + 636 + 5 + 5 + 4 + 0 + 8 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20663655403) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6521035 + ... + 6524202.

Almost surely, 2^20663655408 is an apocalyptic number.

It is an amenable number.

20663655408 is an abundant number, since it is smaller than the sum of its proper divisors (42423115560).

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

20663655408 is a wasteful number, since it uses less digits than its factorization.

20663655408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13045262 (or 13045253 counting only the distinct ones).

The product of its (nonzero) digits is 1036800, while the sum is 45.

The spelling of 20663655408 in words is "twenty billion, six hundred sixty-three million, six hundred fifty-five thousand, four hundred eight".