31913136 has 80 divisors (see below), whose sum is σ = 94597120. Its totient is φ = 10290240.

The previous prime is 31913113. The next prime is 31913177. The reversal of 31913136 is 63131913.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a nude number because it is divisible by every one of its digits.

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, 12201 + ... + 14583.

It is an arithmetic number, because the mean of its divisors is an integer number (1182464).

Almost surely, 2^31913136 is an apocalyptic number.

31913136 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 31913136, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (47298560).

31913136 is an abundant number, since it is smaller than the sum of its proper divisors (62683984).

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

31913136 is a wasteful number, since it uses less digits than its factorization.

31913136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2431 (or 2419 counting only the distinct ones).

The product of its digits is 1458, while the sum is 27.

The square root of 31913136 is about 5649.1712666550. The cubic root of 31913136 is about 317.1926833954.

The spelling of 31913136 in words is "thirty-one million, nine hundred thirteen thousand, one hundred thirty-six".