21121021010000 has 100 divisors (see below), whose sum is σ = 51157111924644. Its totient is φ = 8444937600000.

The previous prime is 21121021009993. The next prime is 21121021010027. The reversal of 21121021010000 is 1012012112.

It can be written as a sum of positive squares in 10 ways, for example, as 13603202815504 + 7517818194496 = 3688252^2 + 2741864^2 .

It is a tau number, because it is divible by the number of its divisors (100).

It is a super-2 number, since 2×21121021010000² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 23977370 + ... + 24842630.

Almost surely, 2^{21121021010000} is an apocalyptic number.

21121021010000 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 21121021010000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25578555962322).

21121021010000 is an abundant number, since it is smaller than the sum of its proper divisors (30036090914644).

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

21121021010000 is an equidigital number, since it uses as much as digits as its factorization.

21121021010000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 867730 (or 867709 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 21121021010000 its reverse (1012012112), we get a palindrome (21122033022112).

The spelling of 21121021010000 in words is "twenty-one trillion, one hundred twenty-one billion, twenty-one million, ten thousand".