31423213 has 4 divisors (see below), whose sum is σ = 32091840. Its totient is φ = 30754588.

The previous prime is 31423187. The next prime is 31423237. The reversal of 31423213 is 31232413.

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 a de Polignac number, because none of the positive numbers 2^k-31423213 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 (31423253) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 334243 + ... + 334336.

It is an arithmetic number, because the mean of its divisors is an integer number (8022960).

Almost surely, 2^31423213 is an apocalyptic number.

It is an amenable number.

31423213 is a deficient number, since it is larger than the sum of its proper divisors (668627).

31423213 is an equidigital number, since it uses as much as digits as its factorization.

31423213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 668626.

The product of its digits is 432, while the sum is 19.

The square root of 31423213 is about 5605.6411765292. The cubic root of 31423213 is about 315.5611497544.

Adding to 31423213 its reverse (31232413), we get a palindrome (62655626).

The spelling of 31423213 in words is "thirty-one million, four hundred twenty-three thousand, two hundred thirteen".