31122213 has 4 divisors (see below), whose sum is σ = 41496288. Its totient is φ = 20748140.

The previous prime is 31122173. The next prime is 31122229. The reversal of 31122213 is 31222113.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 31122213 - 2⁸ = 31121957 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 31122192 and 31122201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31122253) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5187033 + ... + 5187038.

It is an arithmetic number, because the mean of its divisors is an integer number (10374072).

Almost surely, 2^31122213 is an apocalyptic number.

It is an amenable number.

31122213 is a deficient number, since it is larger than the sum of its proper divisors (10374075).

31122213 is a wasteful number, since it uses less digits than its factorization.

31122213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10374074.

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

The square root of 31122213 is about 5578.7286186012. The cubic root of 31122213 is about 314.5503385108.

Adding to 31122213 its reverse (31222113), we get a palindrome (62344326).

The spelling of 31122213 in words is "thirty-one million, one hundred twenty-two thousand, two hundred thirteen".