21020002022111 has 12 divisors (see below), whose sum is σ = 22282305689952. Its totient is φ = 19760595274176.

The previous prime is 21020002022051. The next prime is 21020002022143. The reversal of 21020002022111 is 11122020002012.

It is not a de Polignac number, because 21020002022111 - 2²⁶ = 21019934913247 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21020002012111) 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, 11830970 + ... + 13491176.

It is an arithmetic number, because the mean of its divisors is an integer number (1856858807496).

Almost surely, 2^{21020002022111} is an apocalyptic number.

21020002022111 is a deficient number, since it is larger than the sum of its proper divisors (1262303667841).

21020002022111 is an frugal number, since it uses more digits than its factorization.

21020002022111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1661950 (or 1661087 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 21020002022111 its reverse (11122020002012), we get a palindrome (32142022024123).

The spelling of 21020002022111 in words is "twenty-one trillion, twenty billion, two million, twenty-two thousand, one hundred eleven".