21425355158820 has 48 divisors (see below), whose sum is σ = 61454189438208. Its totient is φ = 5574076138240.

The previous prime is 21425355158761. The next prime is 21425355158839. The reversal of 21425355158820 is 2885155352412.

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, 4354744524 + ... + 4354749443.

It is an arithmetic number, because the mean of its divisors is an integer number (1280295613296).

Almost surely, 2^{21425355158820} is an apocalyptic number.

21425355158820 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21425355158820 is an abundant number, since it is smaller than the sum of its proper divisors (40028834279388).

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

21425355158820 is a wasteful number, since it uses less digits than its factorization.

21425355158820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8709494020 (or 8709494018 counting only the distinct ones).

The product of its (nonzero) digits is 3840000, while the sum is 51.

The spelling of 21425355158820 in words is "twenty-one trillion, four hundred twenty-five billion, three hundred fifty-five million, one hundred fifty-eight thousand, eight hundred twenty".