31213223 has 8 divisors (see below), whose sum is σ = 31993728. Its totient is φ = 30442104.

The previous prime is 31213213. The next prime is 31213243. The reversal of 31213223 is 32231213.

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

It is a cyclic number.

It is not a de Polignac number, because 31213223 - 2⁶ = 31213159 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31213213) 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, 4640 + ... + 9162.

It is an arithmetic number, because the mean of its divisors is an integer number (3999216).

Almost surely, 2^31213223 is an apocalyptic number.

31213223 is a deficient number, since it is larger than the sum of its proper divisors (780505).

31213223 is a wasteful number, since it uses less digits than its factorization.

31213223 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4693.

The product of its digits is 216, while the sum is 17.

The square root of 31213223 is about 5586.8795404949. The cubic root of 31213223 is about 314.8566509925.

Adding to 31213223 its reverse (32231213), we get a palindrome (63444436).

The spelling of 31213223 in words is "thirty-one million, two hundred thirteen thousand, two hundred twenty-three".