31858889 has 2 divisors, whose sum is σ = 31858890. Its totient is φ = 31858888.

The previous prime is 31858873. The next prime is 31858891. The reversal of 31858889 is 98885813.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 30063289 + 1795600 = 5483^2 + 1340^2 .

It is a cyclic number.

It is not a de Polignac number, because 31858889 - 2⁴ = 31858873 is a prime.

Together with 31858891, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (31852889) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15929444 + 15929445.

It is an arithmetic number, because the mean of its divisors is an integer number (15929445).

Almost surely, 2^31858889 is an apocalyptic number.

It is an amenable number.

31858889 is a deficient number, since it is larger than the sum of its proper divisors (1).

31858889 is an equidigital number, since it uses as much as digits as its factorization.

31858889 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 552960, while the sum is 50.

The square root of 31858889 is about 5644.3679008371. The cubic root of 31858889 is about 317.0128566072.

The spelling of 31858889 in words is "thirty-one million, eight hundred fifty-eight thousand, eight hundred eighty-nine".