21112100001021 has 16 divisors (see below), whose sum is σ = 28892855808000. Its totient is φ = 13706048437488.

The previous prime is 21112100001007. The next prime is 21112100001023. The reversal of 21112100001021 is 12010000121112.

It is not a de Polignac number, because 21112100001021 - 2²² = 21112095806717 is a prime.

It is a super-2 number, since 2×21112100001021² (a number of 27 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21112100000988 and 21112100001006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21112100001023) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 376181001 + ... + 376237118.

It is an arithmetic number, because the mean of its divisors is an integer number (1805803488000).

Almost surely, 2^{21112100001021} is an apocalyptic number.

It is an amenable number.

21112100001021 is a deficient number, since it is larger than the sum of its proper divisors (7780755806979).

21112100001021 is a wasteful number, since it uses less digits than its factorization.

21112100001021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 752418368.

The product of its (nonzero) digits is 8, while the sum is 12.

Adding to 21112100001021 its reverse (12010000121112), we get a palindrome (33122100122133).

The spelling of 21112100001021 in words is "twenty-one trillion, one hundred twelve billion, one hundred million, one thousand, twenty-one".