21025164111220 has 96 divisors (see below), whose sum is σ = 45273554726400. Its totient is φ = 8198054513664.

The previous prime is 21025164110983. The next prime is 21025164111221. The reversal of 21025164111220 is 2211146152012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21025164111221) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 993476359 + ... + 993497521.

It is an arithmetic number, because the mean of its divisors is an integer number (471599528400).

Almost surely, 2^{21025164111220} is an apocalyptic number.

21025164111220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21025164111220 is an abundant number, since it is smaller than the sum of its proper divisors (24248390615180).

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

21025164111220 is a wasteful number, since it uses less digits than its factorization.

21025164111220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25417 (or 25415 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 28.

The spelling of 21025164111220 in words is "twenty-one trillion, twenty-five billion, one hundred sixty-four million, one hundred eleven thousand, two hundred twenty".