2021031220 has 24 divisors (see below), whose sum is σ = 4570640424. Its totient is φ = 746226816.

The previous prime is 2021031211. The next prime is 2021031251. The reversal of 2021031220 is 221301202.

It can be written as a sum of positive squares in 4 ways, for example, as 101364624 + 1919666596 = 10068^2 + 43814^2 .

It is a Harshad number since it is a multiple of its sum of digits (13).

It is a self number, because there is not a number n which added to its sum of digits gives 2021031220.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3886339 + ... + 3886858.

It is an arithmetic number, because the mean of its divisors is an integer number (190443351).

Almost surely, 2^2021031220 is an apocalyptic number.

2021031220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2021031220 is an abundant number, since it is smaller than the sum of its proper divisors (2549609204).

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

2021031220 is a wasteful number, since it uses less digits than its factorization.

2021031220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7773219 (or 7773217 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 13.

The square root of 2021031220 is about 44955.8808166407. The cubic root of 2021031220 is about 1264.3219392061.

Adding to 2021031220 its reverse (221301202), we get a palindrome (2242332422).

The spelling of 2021031220 in words is "two billion, twenty-one million, thirty-one thousand, two hundred twenty".