21534370757220 has 24 divisors (see below), whose sum is σ = 60296238120384. Its totient is φ = 5742498868576.

The previous prime is 21534370757177. The next prime is 21534370757243. The reversal of 21534370757220 is 2275707343512.

It is a self number, because there is not a number n which added to its sum of digits gives 21534370757220.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 179453089584 + ... + 179453089703.

It is an arithmetic number, because the mean of its divisors is an integer number (2512343255016).

Almost surely, 2^{21534370757220} is an apocalyptic number.

21534370757220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21534370757220 is an abundant number, since it is smaller than the sum of its proper divisors (38761867363164).

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

21534370757220 is a wasteful number, since it uses less digits than its factorization.

21534370757220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 358906179299 (or 358906179297 counting only the distinct ones).

The product of its (nonzero) digits is 2469600, while the sum is 48.

The spelling of 21534370757220 in words is "twenty-one trillion, five hundred thirty-four billion, three hundred seventy million, seven hundred fifty-seven thousand, two hundred twenty".