21012202002121 has 12 divisors (see below), whose sum is σ = 23100579856816. Its totient is φ = 19098260901720.

The previous prime is 21012202002101. The next prime is 21012202002149. The reversal of 21012202002121 is 12120020221012.

It is a happy number.

It is not a de Polignac number, because 21012202002121 - 2²⁵ = 21012168447689 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21012202002095 and 21012202002104.

It is not an unprimeable number, because it can be changed into a prime (21012202002101) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 16383675 + ... + 17619568.

Almost surely, 2^{21012202002121} is an apocalyptic number.

It is an amenable number.

21012202002121 is a deficient number, since it is larger than the sum of its proper divisors (2088377854695).

21012202002121 is a wasteful number, since it uses less digits than its factorization.

21012202002121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34008372 (or 34008361 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 21012202002121 its reverse (12120020221012), we get a palindrome (33132222223133).

The spelling of 21012202002121 in words is "twenty-one trillion, twelve billion, two hundred two million, two thousand, one hundred twenty-one".