31981887936 has 112 divisors (see below), whose sum is σ = 94178810880. Its totient is φ = 10642717440.

The previous prime is 31981887911. The next prime is 31981887953. The reversal of 31981887936 is 63978818913.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1033651 + ... + 1064141.

It is an arithmetic number, because the mean of its divisors is an integer number (840882240).

Almost surely, 2^31981887936 is an apocalyptic number.

31981887936 is a gapful number since it is divisible by the number (36) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31981887936, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (47089405440).

31981887936 is an abundant number, since it is smaller than the sum of its proper divisors (62196922944).

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

31981887936 is a wasteful number, since it uses less digits than its factorization.

31981887936 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31119 (or 31103 counting only the distinct ones).

The product of its digits is 15676416, while the sum is 63.

The spelling of 31981887936 in words is "thirty-one billion, nine hundred eighty-one million, eight hundred eighty-seven thousand, nine hundred thirty-six".