1312031009 has 2 divisors, whose sum is σ = 1312031010. Its totient is φ = 1312031008.

The previous prime is 1312030999. The next prime is 1312031023. The reversal of 1312031009 is 9001302131.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1030731025 + 281299984 = 32105^2 + 16772^2 .

It is a cyclic number.

It is not a de Polignac number, because 1312031009 - 2²⁰ = 1310982433 is a prime.

It is not a weakly prime, because it can be changed into another prime (1312031029) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 656015504 + 656015505.

It is an arithmetic number, because the mean of its divisors is an integer number (656015505).

Almost surely, 2^1312031009 is an apocalyptic number.

It is an amenable number.

1312031009 is a deficient number, since it is larger than the sum of its proper divisors (1).

1312031009 is an equidigital number, since it uses as much as digits as its factorization.

1312031009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 162, while the sum is 20.

The square root of 1312031009 is about 36221.9685964195. The cubic root of 1312031009 is about 1094.7493595908.

The spelling of 1312031009 in words is "one billion, three hundred twelve million, thirty-one thousand, nine".