21222111221020 has 24 divisors (see below), whose sum is σ = 44790385500000. Its totient is φ = 8446186976832.

The previous prime is 21222111220991. The next prime is 21222111221027. The reversal of 21222111221020 is 2012211122212.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21222111221027) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2666090395 + ... + 2666098354.

It is an arithmetic number, because the mean of its divisors is an integer number (1866266062500).

Almost surely, 2^{21222111221020} is an apocalyptic number.

21222111221020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21222111221020 is an abundant number, since it is smaller than the sum of its proper divisors (23568274278980).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21222111221020 is a wasteful number, since it uses less digits than its factorization.

21222111221020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5332188957 (or 5332188955 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 21222111221020 its reverse (2012211122212), we get a palindrome (23234322343232).

The spelling of 21222111221020 in words is "twenty-one trillion, two hundred twenty-two billion, one hundred eleven million, two hundred twenty-one thousand, twenty".