21453502120 has 64 divisors (see below), whose sum is σ = 49285454400. Its totient is φ = 8402112000.

The previous prime is 21453502067. The next prime is 21453502139. The reversal of 21453502120 is 2120535412.

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, 574252 + ... + 610468.

It is an arithmetic number, because the mean of its divisors is an integer number (770085225).

Almost surely, 2^21453502120 is an apocalyptic number.

21453502120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21453502120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24642727200).

21453502120 is an abundant number, since it is smaller than the sum of its proper divisors (27831952280).

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

21453502120 is a wasteful number, since it uses less digits than its factorization.

21453502120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36538 (or 36534 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 25.

The spelling of 21453502120 in words is "twenty-one billion, four hundred fifty-three million, five hundred two thousand, one hundred twenty".