21222020001021 has 16 divisors (see below), whose sum is σ = 32366959555200. Its totient is φ = 12116127310848.

The previous prime is 21222020000989. The next prime is 21222020001029. The reversal of 21222020001021 is 12010002022212.

It is not a de Polignac number, because 21222020001021 - 2⁵ = 21222020000989 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21222020001029) 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, 447528276 + ... + 447575693.

It is an arithmetic number, because the mean of its divisors is an integer number (2022934972200).

Almost surely, 2^{21222020001021} is an apocalyptic number.

21222020001021 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21222020001021 is a deficient number, since it is larger than the sum of its proper divisors (11144939554179).

21222020001021 is a wasteful number, since it uses less digits than its factorization.

21222020001021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 895105108.

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

Adding to 21222020001021 its reverse (12010002022212), we get a palindrome (33232022023233).

The spelling of 21222020001021 in words is "twenty-one trillion, two hundred twenty-two billion, twenty million, one thousand, twenty-one".