31965381791988 has 72 divisors (see below), whose sum is σ = 75637158912000. Its totient is φ = 10507006043136.

The previous prime is 31965381791887. The next prime is 31965381791989. The reversal of 31965381791988 is 88919718356913.

It is a happy number.

It is a Smith number, since the sum of its digits (78) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31965381791989) 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 23 ways as a sum of consecutive naturals, for example, 327300988 + ... + 327398636.

It is an arithmetic number, because the mean of its divisors is an integer number (1050516096000).

Almost surely, 2^{31965381791988} is an apocalyptic number.

It is an amenable number.

31965381791988 is an abundant number, since it is smaller than the sum of its proper divisors (43671777120012).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

31965381791988 is a wasteful number, since it uses less digits than its factorization.

31965381791988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 102921 (or 102846 counting only the distinct ones).

The product of its digits is 705438720, while the sum is 78.

The spelling of 31965381791988 in words is "thirty-one trillion, nine hundred sixty-five billion, three hundred eighty-one million, seven hundred ninety-one thousand, nine hundred eighty-eight".