31213222 has 8 divisors (see below), whose sum is σ = 48434400. Its totient is φ = 15068424.

The previous prime is 31213213. The next prime is 31213243. The reversal of 31213222 is 22231213.

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

It is a junction number, because it is equal to n+sod(n) for n = 31213196 and 31213205.

It is a congruent number.

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, 269022 + ... + 269137.

It is an arithmetic number, because the mean of its divisors is an integer number (6054300).

Almost surely, 2^31213222 is an apocalyptic number.

31213222 is a deficient number, since it is larger than the sum of its proper divisors (17221178).

31213222 is a wasteful number, since it uses less digits than its factorization.

31213222 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 538190.

The product of its digits is 144, while the sum is 16.

The square root of 31213222 is about 5586.8794509995. The cubic root of 31213222 is about 314.8566476301.

Adding to 31213222 its reverse (22231213), we get a palindrome (53444435).

Subtracting from 31213222 its reverse (22231213), we obtain a square (8982009 = 2997²).

The spelling of 31213222 in words is "thirty-one million, two hundred thirteen thousand, two hundred twenty-two".