31233989 has 2 divisors, whose sum is σ = 31233990. Its totient is φ = 31233988.

The previous prime is 31233973. The next prime is 31234001. The reversal of 31233989 is 98933213.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20884900 + 10349089 = 4570^2 + 3217^2 .

It is an emirp because it is prime and its reverse (98933213) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31233989 - 2⁴ = 31233973 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31233919) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15616994 + 15616995.

It is an arithmetic number, because the mean of its divisors is an integer number (15616995).

Almost surely, 2^31233989 is an apocalyptic number.

It is an amenable number.

31233989 is a deficient number, since it is larger than the sum of its proper divisors (1).

31233989 is an equidigital number, since it uses as much as digits as its factorization.

31233989 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 34992, while the sum is 38.

The square root of 31233989 is about 5588.7376928963. The cubic root of 31233989 is about 314.9264596949.

The spelling of 31233989 in words is "thirty-one million, two hundred thirty-three thousand, nine hundred eighty-nine".