31117812 has 72 divisors (see below), whose sum is σ = 82672800. Its totient is φ = 9092160.

The previous prime is 31117799. The next prime is 31117813. The reversal of 31117812 is 21871113.

It is a happy number.

It is a super-3 number, since 3×31117812³ (a number of 23 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31117813) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 41739 + ... + 42477.

Almost surely, 2^31117812 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 31117812, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41336400).

31117812 is an abundant number, since it is smaller than the sum of its proper divisors (51554988).

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

31117812 is a wasteful number, since it uses less digits than its factorization.

31117812 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 797 (or 784 counting only the distinct ones).

The product of its digits is 336, while the sum is 24.

The square root of 31117812 is about 5578.3341599442. The cubic root of 31117812 is about 314.5355109310.

Adding to 31117812 its reverse (21871113), we get a palindrome (52988925).

The spelling of 31117812 in words is "thirty-one million, one hundred seventeen thousand, eight hundred twelve".