31113440 has 48 divisors (see below), whose sum is σ = 74018448. Its totient is φ = 12358656.

The previous prime is 31113413. The next prime is 31113443. The reversal of 31113440 is 4431113.

It is a super-2 number, since 2×31113440² = 1936092297267200, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31113443) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25484 + ... + 26676.

It is an arithmetic number, because the mean of its divisors is an integer number (1542051).

Almost surely, 2^31113440 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 31113440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37009224).

31113440 is an abundant number, since it is smaller than the sum of its proper divisors (42905008).

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

31113440 is a wasteful number, since it uses less digits than its factorization.

31113440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1371 (or 1363 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 17.

The square root of 31113440 is about 5577.9422729175. The cubic root of 31113440 is about 314.5207796718.

Adding to 31113440 its reverse (4431113), we get a palindrome (35544553).

The spelling of 31113440 in words is "thirty-one million, one hundred thirteen thousand, four hundred forty".