21220022020 has 24 divisors (see below), whose sum is σ = 44663572800. Its totient is φ = 8468670432.

The previous prime is 21220021987. The next prime is 21220022023. The reversal of 21220022020 is 2022002212.

It is not an unprimeable number, because it can be changed into a prime (21220022023) 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, 1199650 + ... + 1217209.

It is an arithmetic number, because the mean of its divisors is an integer number (1860982200).

Almost surely, 2^21220022020 is an apocalyptic number.

21220022020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21220022020 is an abundant number, since it is smaller than the sum of its proper divisors (23443550780).

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

21220022020 is a wasteful number, since it uses less digits than its factorization.

21220022020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2417307 (or 2417305 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 13.

Adding to 21220022020 its reverse (2022002212), we get a palindrome (23242024232).

The spelling of 21220022020 in words is "twenty-one billion, two hundred twenty million, twenty-two thousand, twenty".