31771531968 has 224 divisors, whose sum is σ = 95226347520. Its totient is φ = 9261696000.

The previous prime is 31771531963. The next prime is 31771531997. The reversal of 31771531968 is 86913517713.

It is a self number, because there is not a number n which added to its sum of digits gives 31771531968.

It is not an unprimeable number, because it can be changed into a prime (31771531963) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 11718133 + ... + 11720843.

Almost surely, 2^31771531968 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31771531968, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (47613173760).

31771531968 is an abundant number, since it is smaller than the sum of its proper divisors (63454815552).

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

31771531968 is a wasteful number, since it uses less digits than its factorization.

31771531968 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2947 (or 2937 counting only the distinct ones).

The product of its digits is 952560, while the sum is 51.

The spelling of 31771531968 in words is "thirty-one billion, seven hundred seventy-one million, five hundred thirty-one thousand, nine hundred sixty-eight".