31379816 has 32 divisors (see below), whose sum is σ = 64569960. Its totient is φ = 14207232.

The previous prime is 31379767. The next prime is 31379819. The reversal of 31379816 is 61897313.

It can be written as a sum of positive squares in 4 ways, for example, as 18748900 + 12630916 = 4330^2 + 3554^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 31379816.

It is not an unprimeable number, because it can be changed into a prime (31379819) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2666 + ... + 8358.

Almost surely, 2^31379816 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 31379816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32284980).

31379816 is an abundant number, since it is smaller than the sum of its proper divisors (33190144).

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

31379816 is a wasteful number, since it uses less digits than its factorization.

31379816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5765 (or 5761 counting only the distinct ones).

The product of its digits is 27216, while the sum is 38.

The square root of 31379816 is about 5601.7690063051. The cubic root of 31379816 is about 315.4158143483.

The spelling of 31379816 in words is "thirty-one million, three hundred seventy-nine thousand, eight hundred sixteen".