21105550024 has 16 divisors (see below), whose sum is σ = 42616976220. Its totient is φ = 9741023040.

The previous prime is 21105550001. The next prime is 21105550051. The reversal of 21105550024 is 42005550112.

It can be written as a sum of positive squares in 2 ways, for example, as 20368427524 + 737122500 = 142718^2 + 27150^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 101468887 + ... + 101469094.

Almost surely, 2^21105550024 is an apocalyptic number.

It is an amenable number.

21105550024 is an abundant number, since it is smaller than the sum of its proper divisors (21511426196).

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

21105550024 is a wasteful number, since it uses less digits than its factorization.

21105550024 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 202938000 (or 202937996 counting only the distinct ones).

The product of its (nonzero) digits is 2000, while the sum is 25.

The spelling of 21105550024 in words is "twenty-one billion, one hundred five million, five hundred fifty thousand, twenty-four".