31398893 has 4 divisors (see below), whose sum is σ = 31628220. Its totient is φ = 31169568.

The previous prime is 31398889. The next prime is 31398923. The reversal of 31398893 is 39889313.

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 5866084 + 25532809 = 2422^2 + 5053^2 .

It is a cyclic number.

It is not a de Polignac number, because 31398893 - 2² = 31398889 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 (31398823) 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, 114458 + ... + 114731.

It is an arithmetic number, because the mean of its divisors is an integer number (7907055).

Almost surely, 2^31398893 is an apocalyptic number.

It is an amenable number.

31398893 is a deficient number, since it is larger than the sum of its proper divisors (229327).

31398893 is a wasteful number, since it uses less digits than its factorization.

31398893 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 229326.

The product of its digits is 139968, while the sum is 44.

The square root of 31398893 is about 5603.4715132675. The cubic root of 31398893 is about 315.4797192114.

The spelling of 31398893 in words is "thirty-one million, three hundred ninety-eight thousand, eight hundred ninety-three".