31894213 has 4 divisors (see below), whose sum is σ = 34347628. Its totient is φ = 29440800.

The previous prime is 31894207. The next prime is 31894231. The reversal of 31894213 is 31249813.

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 12945604 + 18948609 = 3598^2 + 4353^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31894213 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 (31894243) 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, 1226688 + ... + 1226713.

It is an arithmetic number, because the mean of its divisors is an integer number (8586907).

Almost surely, 2^31894213 is an apocalyptic number.

It is an amenable number.

31894213 is a deficient number, since it is larger than the sum of its proper divisors (2453415).

31894213 is a wasteful number, since it uses less digits than its factorization.

31894213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2453414.

The product of its digits is 5184, while the sum is 31.

The square root of 31894213 is about 5647.4961708708. The cubic root of 31894213 is about 317.1299775148.

The spelling of 31894213 in words is "thirty-one million, eight hundred ninety-four thousand, two hundred thirteen".