20212656220 has 72 divisors (see below), whose sum is σ = 45101175840. Its totient is φ = 7606515840.

The previous prime is 20212656157. The next prime is 20212656223. The reversal of 20212656220 is 2265621202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20212656223) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 629721 + ... + 661039.

It is an arithmetic number, because the mean of its divisors is an integer number (626405220).

Almost surely, 2^20212656220 is an apocalyptic number.

20212656220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20212656220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22550587920).

20212656220 is an abundant number, since it is smaller than the sum of its proper divisors (24888519620).

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

20212656220 is a wasteful number, since it uses less digits than its factorization.

20212656220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31435 (or 31410 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 28.

The spelling of 20212656220 in words is "twenty billion, two hundred twelve million, six hundred fifty-six thousand, two hundred twenty".