20312221920 has 96 divisors (see below), whose sum is σ = 64143666720. Its totient is φ = 5403033600.

The previous prime is 20312221901. The next prime is 20312221921. The reversal of 20312221920 is 2912221302.

It is a tau number, because it is divible by the number of its divisors (96).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20312221921) 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, 139716 + ... + 245244.

It is an arithmetic number, because the mean of its divisors is an integer number (668163195).

Almost surely, 2^20312221920 is an apocalyptic number.

20312221920 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 20312221920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32071833360).

20312221920 is an abundant number, since it is smaller than the sum of its proper divisors (43831444800).

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

20312221920 is a wasteful number, since it uses less digits than its factorization.

20312221920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 105948 (or 105940 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 24.

The spelling of 20312221920 in words is "twenty billion, three hundred twelve million, two hundred twenty-one thousand, nine hundred twenty".