20231021220 has 96 divisors (see below), whose sum is σ = 57913228800. Its totient is φ = 5274576384.

The previous prime is 20231021219. The next prime is 20231021233. The reversal of 20231021220 is 2212013202.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 20231021220.

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, 3124146 + ... + 3130614.

It is an arithmetic number, because the mean of its divisors is an integer number (603262800).

Almost surely, 2^20231021220 is an apocalyptic number.

20231021220 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 20231021220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28956614400).

20231021220 is an abundant number, since it is smaller than the sum of its proper divisors (37682207580).

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

20231021220 is a wasteful number, since it uses less digits than its factorization.

20231021220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7637 (or 7635 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 15.

Adding to 20231021220 its reverse (2212013202), we get a palindrome (22443034422).

The spelling of 20231021220 in words is "twenty billion, two hundred thirty-one million, twenty-one thousand, two hundred twenty".