2031131221 has 8 divisors (see below), whose sum is σ = 2324168640. Its totient is φ = 1738812768.

The previous prime is 2031131189. The next prime is 2031131231. The reversal of 2031131221 is 1221311302.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 2031131221 - 2⁵ = 2031131189 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2031131195 and 2031131204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2031131231) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 173671 + ... + 184996.

It is an arithmetic number, because the mean of its divisors is an integer number (290521080).

Almost surely, 2^2031131221 is an apocalyptic number.

It is an amenable number.

2031131221 is a deficient number, since it is larger than the sum of its proper divisors (293037419).

2031131221 is an equidigital number, since it uses as much as digits as its factorization.

2031131221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 359483.

The product of its (nonzero) digits is 72, while the sum is 16.

The square root of 2031131221 is about 45068.0731893433. The cubic root of 2031131221 is about 1266.4245687431.

Adding to 2031131221 its reverse (1221311302), we get a palindrome (3252442523).

The spelling of 2031131221 in words is "two billion, thirty-one million, one hundred thirty-one thousand, two hundred twenty-one".