2131021220 has 48 divisors (see below), whose sum is σ = 4665378816. Its totient is φ = 816720000.

The previous prime is 2131021169. The next prime is 2131021241. The reversal of 2131021220 is 221201312.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 2131021195 and 2131021204.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 45605 + ... + 79635.

It is an arithmetic number, because the mean of its divisors is an integer number (97195392).

Almost surely, 2^2131021220 is an apocalyptic number.

2131021220 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 2131021220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2332689408).

2131021220 is an abundant number, since it is smaller than the sum of its proper divisors (2534357596).

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

2131021220 is a wasteful number, since it uses less digits than its factorization.

2131021220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34172 (or 34170 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 14.

The square root of 2131021220 is about 46162.9853887289. The cubic root of 2131021220 is about 1286.8539445094.

Adding to 2131021220 its reverse (221201312), we get a palindrome (2352222532).

The spelling of 2131021220 in words is "two billion, one hundred thirty-one million, twenty-one thousand, two hundred twenty".