31431716221 has 8 divisors (see below), whose sum is σ = 31729257560. Its totient is φ = 31134341952.

The previous prime is 31431716213. The next prime is 31431716237. The reversal of 31431716221 is 12261713413.

It can be written as a sum of positive squares in 4 ways, for example, as 5836196025 + 25595520196 = 76395^2 + 159986^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 31431716221 - 2³ = 31431716213 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 (31431716521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 353911 + ... + 433723.

It is an arithmetic number, because the mean of its divisors is an integer number (3966157195).

Almost surely, 2^31431716221 is an apocalyptic number.

It is an amenable number.

31431716221 is a deficient number, since it is larger than the sum of its proper divisors (297541339).

31431716221 is a wasteful number, since it uses less digits than its factorization.

31431716221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83535.

The product of its digits is 6048, while the sum is 31.

The spelling of 31431716221 in words is "thirty-one billion, four hundred thirty-one million, seven hundred sixteen thousand, two hundred twenty-one".