21002212020021 has 16 divisors (see below), whose sum is σ = 28039214070336. Its totient is φ = 13983354043776.

The previous prime is 21002212020017. The next prime is 21002212020037. The reversal of 21002212020021 is 12002021220012.

It is not a de Polignac number, because 21002212020021 - 2² = 21002212020017 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21002212020821) 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, 5712921 + ... + 8639553.

It is an arithmetic number, because the mean of its divisors is an integer number (1752450879396).

Almost surely, 2^{21002212020021} is an apocalyptic number.

It is an amenable number.

21002212020021 is a deficient number, since it is larger than the sum of its proper divisors (7037002050315).

21002212020021 is a wasteful number, since it uses less digits than its factorization.

21002212020021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2929732.

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 21002212020021 its reverse (12002021220012), we get a palindrome (33004233240033).

The spelling of 21002212020021 in words is "twenty-one trillion, two billion, two hundred twelve million, twenty thousand, twenty-one".