31122013 has 8 divisors (see below), whose sum is σ = 34973568. Its totient is φ = 27478704.

The previous prime is 31121999. The next prime is 31122023. The reversal of 31122013 is 31022113.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31122013 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (13).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31121984 and 31122002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31122023) 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, 51745 + ... + 52342.

It is an arithmetic number, because the mean of its divisors is an integer number (4371696).

Almost surely, 2^31122013 is an apocalyptic number.

It is an amenable number.

31122013 is a deficient number, since it is larger than the sum of its proper divisors (3851555).

31122013 is a wasteful number, since it uses less digits than its factorization.

31122013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 104123.

The product of its (nonzero) digits is 36, while the sum is 13.

The square root of 31122013 is about 5578.7106933412. The cubic root of 31122013 is about 314.5496647134.

Adding to 31122013 its reverse (31022113), we get a palindrome (62144126).

The spelling of 31122013 in words is "thirty-one million, one hundred twenty-two thousand, thirteen".