31130420 has 24 divisors (see below), whose sum is σ = 66112200. Its totient is φ = 12311552.

The previous prime is 31130419. The next prime is 31130423. The reversal of 31130420 is 2403113.

It can be written as a sum of positive squares in 4 ways, for example, as 1493284 + 29637136 = 1222^2 + 5444^2 .

It is a junction number, because it is equal to n+sod(n) for n = 31130395 and 31130404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31130423) 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, 6965 + ... + 10524.

It is an arithmetic number, because the mean of its divisors is an integer number (2754675).

Almost surely, 2^31130420 is an apocalyptic number.

It is an amenable number.

31130420 is an abundant number, since it is smaller than the sum of its proper divisors (34981780).

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

31130420 is a wasteful number, since it uses less digits than its factorization.

31130420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17587 (or 17585 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 14.

The square root of 31130420 is about 5579.4641319754. The cubic root of 31130420 is about 314.5779852996.

Adding to 31130420 its reverse (2403113), we get a palindrome (33533533).

The spelling of 31130420 in words is "thirty-one million, one hundred thirty thousand, four hundred twenty".