31122320 has 20 divisors (see below), whose sum is σ = 72359580. Its totient is φ = 12448896.

The previous prime is 31122293. The next prime is 31122331. The reversal of 31122320 is 2322113.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 23658496 + 7463824 = 4864^2 + 2732^2 .

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

It is a junction number, because it is equal to n+sod(n) for n = 31122295 and 31122304.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 194435 + ... + 194594.

It is an arithmetic number, because the mean of its divisors is an integer number (3617979).

Almost surely, 2^31122320 is an apocalyptic number.

It is an amenable number.

31122320 is an abundant number, since it is smaller than the sum of its proper divisors (41237260).

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

31122320 is a wasteful number, since it uses less digits than its factorization.

31122320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 389042 (or 389036 counting only the distinct ones).

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

The square root of 31122320 is about 5578.7382085916. The cubic root of 31122320 is about 314.5506989913.

Adding to 31122320 its reverse (2322113), we get a palindrome (33444433).

The spelling of 31122320 in words is "thirty-one million, one hundred twenty-two thousand, three hundred twenty".