31285889 has 2 divisors, whose sum is σ = 31285890. Its totient is φ = 31285888.

The previous prime is 31285853. The next prime is 31285901. The reversal of 31285889 is 98858213.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 25959025 + 5326864 = 5095^2 + 2308^2 .

It is a cyclic number.

It is not a de Polignac number, because 31285889 - 2⁸ = 31285633 is a prime.

It is not a weakly prime, because it can be changed into another prime (31281889) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15642944 + 15642945.

It is an arithmetic number, because the mean of its divisors is an integer number (15642945).

Almost surely, 2^31285889 is an apocalyptic number.

It is an amenable number.

31285889 is a deficient number, since it is larger than the sum of its proper divisors (1).

31285889 is an equidigital number, since it uses as much as digits as its factorization.

31285889 is an evil number, because the sum of its binary digits is even.

The product of its digits is 138240, while the sum is 44.

The square root of 31285889 is about 5593.3790323918. The cubic root of 31285889 is about 315.1007958276.

The spelling of 31285889 in words is "thirty-one million, two hundred eighty-five thousand, eight hundred eighty-nine".