1311203009 has 2 divisors, whose sum is σ = 1311203010. Its totient is φ = 1311203008.

The previous prime is 1311202993. The next prime is 1311203017. The reversal of 1311203009 is 9003021131.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1209091984 + 102111025 = 34772^2 + 10105^2 .

It is a cyclic number.

It is not a de Polignac number, because 1311203009 - 2⁴ = 1311202993 is a prime.

It is not a weakly prime, because it can be changed into another prime (1311203609) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 655601504 + 655601505.

It is an arithmetic number, because the mean of its divisors is an integer number (655601505).

Almost surely, 2^1311203009 is an apocalyptic number.

It is an amenable number.

1311203009 is a deficient number, since it is larger than the sum of its proper divisors (1).

1311203009 is an equidigital number, since it uses as much as digits as its factorization.

1311203009 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 1311203009 is about 36210.5372647245. The cubic root of 1311203009 is about 1094.5190186886.

The spelling of 1311203009 in words is "one billion, three hundred eleven million, two hundred three thousand, nine".