21900550055500 has 48 divisors (see below), whose sum is σ = 49910401404864. Its totient is φ = 8379340886400.

The previous prime is 21900550055459. The next prime is 21900550055663. The reversal of 21900550055500 is 555005500912.

It is a super-2 number, since 2×21900550055500² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21900550055500.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 952186329 + ... + 952209328.

It is an arithmetic number, because the mean of its divisors is an integer number (1039800029268).

Almost surely, 2^{21900550055500} is an apocalyptic number.

21900550055500 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21900550055500 is an abundant number, since it is smaller than the sum of its proper divisors (28009851349364).

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

21900550055500 is a wasteful number, since it uses less digits than its factorization.

21900550055500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1904395699 (or 1904395687 counting only the distinct ones).

The product of its (nonzero) digits is 56250, while the sum is 37.

The spelling of 21900550055500 in words is "twenty-one trillion, nine hundred billion, five hundred fifty million, fifty-five thousand, five hundred".