31321489 has 2 divisors, whose sum is σ = 31321490. Its totient is φ = 31321488.

The previous prime is 31321483. The next prime is 31321513. The reversal of 31321489 is 98412313.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 26625600 + 4695889 = 5160^2 + 2167^2 .

It is a cyclic number.

It is not a de Polignac number, because 31321489 - 2⁵ = 31321457 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 31321489.

It is not a weakly prime, because it can be changed into another prime (31321483) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15660744 + 15660745.

It is an arithmetic number, because the mean of its divisors is an integer number (15660745).

Almost surely, 2^31321489 is an apocalyptic number.

It is an amenable number.

31321489 is a deficient number, since it is larger than the sum of its proper divisors (1).

31321489 is an equidigital number, since it uses as much as digits as its factorization.

31321489 is an evil number, because the sum of its binary digits is even.

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

The square root of 31321489 is about 5596.5604615692. The cubic root of 31321489 is about 315.2202675401.

The spelling of 31321489 in words is "thirty-one million, three hundred twenty-one thousand, four hundred eighty-nine".