31251542221 has 16 divisors (see below), whose sum is σ = 33582669120. Its totient is φ = 28978410240.

The previous prime is 31251542207. The next prime is 31251542237. The reversal of 31251542221 is 12224515213.

It is a happy number.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31251542221 is a prime.

It is a super-2 number, since 2×31251542221² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 31251542221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31251542921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 259075 + ... + 360031.

It is an arithmetic number, because the mean of its divisors is an integer number (2098916820).

Almost surely, 2^31251542221 is an apocalyptic number.

It is an amenable number.

31251542221 is a deficient number, since it is larger than the sum of its proper divisors (2331126899).

31251542221 is a wasteful number, since it uses less digits than its factorization.

31251542221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 101244.

The product of its digits is 4800, while the sum is 28.

The spelling of 31251542221 in words is "thirty-one billion, two hundred fifty-one million, five hundred forty-two thousand, two hundred twenty-one".