21202002210021 has 12 divisors (see below), whose sum is σ = 29835504496512. Its totient is φ = 13390738237224.

The previous prime is 21202002210019. The next prime is 21202002210029. The reversal of 21202002210021 is 12001220020212.

It is not a de Polignac number, because 21202002210021 - 2¹ = 21202002210019 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21202002210029) 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, 9788550261 + ... + 9788552426.

It is an arithmetic number, because the mean of its divisors is an integer number (2486292041376).

Almost surely, 2^{21202002210021} is an apocalyptic number.

It is an amenable number.

21202002210021 is a deficient number, since it is larger than the sum of its proper divisors (8633502286491).

21202002210021 is a wasteful number, since it uses less digits than its factorization.

21202002210021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19577102728 (or 19577102709 counting only the distinct ones).

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

Adding to 21202002210021 its reverse (12001220020212), we get a palindrome (33203222230233).

The spelling of 21202002210021 in words is "twenty-one trillion, two hundred two billion, two million, two hundred ten thousand, twenty-one".