21550500530 has 64 divisors (see below), whose sum is σ = 44037181440. Its totient is φ = 7527396096.

The previous prime is 21550500523. The next prime is 21550500553. The reversal of 21550500530 is 3500505512.

It is a Harshad number since it is a multiple of its sum of digits (26).

It is a self number, because there is not a number n which added to its sum of digits gives 21550500530.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1804559 + ... + 1816461.

It is an arithmetic number, because the mean of its divisors is an integer number (688080960).

Almost surely, 2^21550500530 is an apocalyptic number.

21550500530 is an abundant number, since it is smaller than the sum of its proper divisors (22486680910).

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

21550500530 is a wasteful number, since it uses less digits than its factorization.

21550500530 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12675.

The product of its (nonzero) digits is 3750, while the sum is 26.

The spelling of 21550500530 in words is "twenty-one billion, five hundred fifty million, five hundred thousand, five hundred thirty".