31998893 has 4 divisors (see below), whose sum is σ = 32437308. Its totient is φ = 31560480.

The previous prime is 31998877. The next prime is 31998937. The reversal of 31998893 is 39889913.

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 22401289 + 9597604 = 4733^2 + 3098^2 .

It is a cyclic number.

It is not a de Polignac number, because 31998893 - 2⁴ = 31998877 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 (31998193) 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, 219098 + ... + 219243.

It is an arithmetic number, because the mean of its divisors is an integer number (8109327).

Almost surely, 2^31998893 is an apocalyptic number.

It is an amenable number.

31998893 is a deficient number, since it is larger than the sum of its proper divisors (438415).

31998893 is an equidigital number, since it uses as much as digits as its factorization.

31998893 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 438414.

The product of its digits is 419904, while the sum is 50.

The square root of 31998893 is about 5656.7564027453. The cubic root of 31998893 is about 317.4765494077.

The spelling of 31998893 in words is "thirty-one million, nine hundred ninety-eight thousand, eight hundred ninety-three".