20201221220 has 96 divisors (see below), whose sum is σ = 43823203200. Its totient is φ = 7819075584.

The previous prime is 20201221213. The next prime is 20201221231. The reversal of 20201221220 is 2212210202.

It is a junction number, because it is equal to n+sod(n) for n = 20201221195 and 20201221204.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 24367766 + ... + 24368594.

It is an arithmetic number, because the mean of its divisors is an integer number (456491700).

Almost surely, 2^20201221220 is an apocalyptic number.

20201221220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20201221220 is an abundant number, since it is smaller than the sum of its proper divisors (23621981980).

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

20201221220 is a wasteful number, since it uses less digits than its factorization.

20201221220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1197 (or 1195 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 14.

Adding to 20201221220 its reverse (2212210202), we get a palindrome (22413431422).

The spelling of 20201221220 in words is "twenty billion, two hundred one million, two hundred twenty-one thousand, two hundred twenty".