31232213 has 4 divisors (see below), whose sum is σ = 33069420. Its totient is φ = 29395008.

The previous prime is 31232207. The next prime is 31232231. The reversal of 31232213 is 31223213.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 16662724 + 14569489 = 4082^2 + 3817^2 .

It is a cyclic number.

It is not a de Polignac number, because 31232213 - 2¹² = 31228117 is a prime.

It is a super-2 number, since 2×31232213² = 1950902257754738, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (17), and also a Moran number because the ratio is a prime number: 1837189 = 31232213 / (3 + 1 + 2 + 3 + 2 + 2 + 1 + 3).

It is a junction number, because it is equal to n+sod(n) for n = 31232191 and 31232200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31232203) by changing a digit.

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, 918578 + ... + 918611.

It is an arithmetic number, because the mean of its divisors is an integer number (8267355).

Almost surely, 2^31232213 is an apocalyptic number.

It is an amenable number.

31232213 is a deficient number, since it is larger than the sum of its proper divisors (1837207).

31232213 is a wasteful number, since it uses less digits than its factorization.

31232213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1837206.

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

The square root of 31232213 is about 5588.5787996592. The cubic root of 31232213 is about 314.9204905566.

Adding to 31232213 its reverse (31223213), we get a palindrome (62455426).

The spelling of 31232213 in words is "thirty-one million, two hundred thirty-two thousand, two hundred thirteen".