31120 has 20 divisors (see below), whose sum is σ = 72540. Its totient is φ = 12416.

The previous prime is 31091. The next prime is 31121. The reversal of 31120 is 2113.

It can be written as a sum of positive squares in 2 ways, for example, as 9216 + 21904 = 96^2 + 148^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is not an unprimeable number, because it can be changed into a prime (31121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 115 + ... + 274.

It is an arithmetic number, because the mean of its divisors is an integer number (3627).

2³¹¹²⁰ is an apocalyptic number.

It is an amenable number.

31120 is an abundant number, since it is smaller than the sum of its proper divisors (41420).

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

It is a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36270).

31120 is a wasteful number, since it uses less digits than its factorization.

31120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 402 (or 396 counting only the distinct ones).

The product of its (nonzero) digits is 6, while the sum is 7.

The square root of 31120 is about 176.4086165696. The cubic root of 31120 is about 31.4542882781.

Adding to 31120 its reverse (2113), we get a palindrome (33233).

It can be divided in two parts, 31 and 120, that added together give a palindrome (151).

The spelling of 31120 in words is "thirty-one thousand, one hundred twenty".