31983940 has 48 divisors (see below), whose sum is σ = 70318080. Its totient is φ = 12205440.

The previous prime is 31983937. The next prime is 31983949. The reversal of 31983940 is 4938913.

It is a self number, because there is not a number n which added to its sum of digits gives 31983940.

It is not an unprimeable number, because it can be changed into a prime (31983949) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 48654 + ... + 49306.

It is an arithmetic number, because the mean of its divisors is an integer number (1464960).

Almost surely, 2^31983940 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 31983940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35159040).

31983940 is an abundant number, since it is smaller than the sum of its proper divisors (38334140).

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

31983940 is a wasteful number, since it uses less digits than its factorization.

31983940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 772 (or 770 counting only the distinct ones).

The product of its (nonzero) digits is 23328, while the sum is 37.

The square root of 31983940 is about 5655.4345544794. The cubic root of 31983940 is about 317.4270897125.

It can be divided in two parts, 31983 and 940, that added together give a palindrome (32923).

The spelling of 31983940 in words is "thirty-one million, nine hundred eighty-three thousand, nine hundred forty".