20558556640 has 48 divisors (see below), whose sum is σ = 48694595040. Its totient is φ = 8202257920.

The previous prime is 20558556631. The next prime is 20558556701. The reversal of 20558556640 is 4665585502.

It is a super-2 number, since 2×20558556640² (a number of 21 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (46) 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, 102916 + ... + 227395.

It is an arithmetic number, because the mean of its divisors is an integer number (1014470730).

Almost surely, 2^20558556640 is an apocalyptic number.

20558556640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20558556640 is an abundant number, since it is smaller than the sum of its proper divisors (28136038400).

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

20558556640 is a wasteful number, since it uses less digits than its factorization.

20558556640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 330715 (or 330707 counting only the distinct ones).

The product of its (nonzero) digits is 1440000, while the sum is 46.

The spelling of 20558556640 in words is "twenty billion, five hundred fifty-eight million, five hundred fifty-six thousand, six hundred forty".