31132113131221 has 4 divisors (see below), whose sum is σ = 31154656299244. Its totient is φ = 31109569963200.

The previous prime is 31132113131219. The next prime is 31132113131261. The reversal of 31132113131221 is 12213131123113.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 25894816803025 + 5237296328196 = 5088695^2 + 2288514^2 .

It is a cyclic number.

It is not a de Polignac number, because 31132113131221 - 2¹ = 31132113131219 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31132113131261) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11271581940 + ... + 11271584701.

It is an arithmetic number, because the mean of its divisors is an integer number (7788664074811).

Almost surely, 2^{31132113131221} is an apocalyptic number.

It is an amenable number.

31132113131221 is a deficient number, since it is larger than the sum of its proper divisors (22543168023).

31132113131221 is a wasteful number, since it uses less digits than its factorization.

31132113131221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22543168022.

The product of its digits is 648, while the sum is 25.

Adding to 31132113131221 its reverse (12213131123113), we get a palindrome (43345244254334).

The spelling of 31132113131221 in words is "thirty-one trillion, one hundred thirty-two billion, one hundred thirteen million, one hundred thirty-one thousand, two hundred twenty-one".