31112009 has 2 divisors, whose sum is σ = 31112010. Its totient is φ = 31112008.

The previous prime is 31111999. The next prime is 31112021. The reversal of 31112009 is 90021113.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 25603600 + 5508409 = 5060^2 + 2347^2 .

It is a cyclic number.

It is not a de Polignac number, because 31112009 - 2⁸ = 31111753 is a prime.

It is not a weakly prime, because it can be changed into another prime (31112209) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15556004 + 15556005.

It is an arithmetic number, because the mean of its divisors is an integer number (15556005).

Almost surely, 2^31112009 is an apocalyptic number.

It is an amenable number.

31112009 is a deficient number, since it is larger than the sum of its proper divisors (1).

31112009 is an equidigital number, since it uses as much as digits as its factorization.

31112009 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 54, while the sum is 17.

The square root of 31112009 is about 5577.8139983330. The cubic root of 31112009 is about 314.5159576813.

The spelling of 31112009 in words is "thirty-one million, one hundred twelve thousand, nine".