31302130221 has 12 divisors (see below), whose sum is σ = 45215757340. Its totient is φ = 20867362560.

The previous prime is 31302130213. The next prime is 31302130261. The reversal of 31302130221 is 12203120313.

31302130221 is a `hidden beast` number, since 313 + 0 + 2 + 130 + 221 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 29692114596 + 1610015625 = 172314^2 + 40125^2 .

It is not a de Polignac number, because 31302130221 - 2³ = 31302130213 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31302130194 and 31302130203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31302130201) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 391095 + ... + 464283.

Almost surely, 2^31302130221 is an apocalyptic number.

It is an amenable number.

31302130221 is a deficient number, since it is larger than the sum of its proper divisors (13913627119).

31302130221 is a wasteful number, since it uses less digits than its factorization.

31302130221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 120716 (or 120713 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 18.

Adding to 31302130221 its reverse (12203120313), we get a palindrome (43505250534).

The spelling of 31302130221 in words is "thirty-one billion, three hundred two million, one hundred thirty thousand, two hundred twenty-one".