21202100001021 has 32 divisors (see below), whose sum is σ = 30234981427200. Its totient is φ = 13183709482944.

The previous prime is 21202100001011. The next prime is 21202100001031. The reversal of 21202100001021 is 12010000120212.

It is an interprime number because it is at equal distance from previous prime (21202100001011) and next prime (21202100001031).

It is not a de Polignac number, because 21202100001021 - 2²⁷ = 21201965783293 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21202100000988 and 21202100001006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21202100001011) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4187686 + ... + 7742151.

It is an arithmetic number, because the mean of its divisors is an integer number (944843169600).

Almost surely, 2^{21202100001021} is an apocalyptic number.

It is an amenable number.

21202100001021 is a deficient number, since it is larger than the sum of its proper divisors (9032881426179).

21202100001021 is a wasteful number, since it uses less digits than its factorization.

21202100001021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11930505.

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 21202100001021 its reverse (12010000120212), we get a palindrome (33212100121233).

The spelling of 21202100001021 in words is "twenty-one trillion, two hundred two billion, one hundred million, one thousand, twenty-one".