31113420 has 96 divisors (see below), whose sum is σ = 94917312. Its totient is φ = 7569408.

The previous prime is 31113413. The next prime is 31113443. The reversal of 31113420 is 2431113.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 31113420.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 87964 + ... + 88316.

It is an arithmetic number, because the mean of its divisors is an integer number (988722).

Almost surely, 2^31113420 is an apocalyptic number.

31113420 is a gapful number since it is divisible by the number (30) 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 31113420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (47458656).

31113420 is an abundant number, since it is smaller than the sum of its proper divisors (63803892).

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

31113420 is a wasteful number, since it uses less digits than its factorization.

31113420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 491 (or 489 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 15.

The square root of 31113420 is about 5577.9404801414. The cubic root of 31113420 is about 314.5207122795.

Adding to 31113420 its reverse (2431113), we get a palindrome (33544533).

It can be divided in two parts, 311 and 13420, that added together give a palindrome (13731).

The spelling of 31113420 in words is "thirty-one million, one hundred thirteen thousand, four hundred twenty".