1331376209 has 2 divisors, whose sum is σ = 1331376210. Its totient is φ = 1331376208.

The previous prime is 1331376161. The next prime is 1331376223. The reversal of 1331376209 is 9026731331.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1275918400 + 55457809 = 35720^2 + 7447^2 .

It is a cyclic number.

It is not a de Polignac number, because 1331376209 - 2²⁰ = 1330327633 is a prime.

It is not a weakly prime, because it can be changed into another prime (1331376269) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 665688104 + 665688105.

It is an arithmetic number, because the mean of its divisors is an integer number (665688105).

Almost surely, 2^1331376209 is an apocalyptic number.

It is an amenable number.

1331376209 is a deficient number, since it is larger than the sum of its proper divisors (1).

1331376209 is an equidigital number, since it uses as much as digits as its factorization.

1331376209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 20412, while the sum is 35.

The square root of 1331376209 is about 36488.0282969634. The cubic root of 1331376209 is about 1100.1036290800.

The spelling of 1331376209 in words is "one billion, three hundred thirty-one million, three hundred seventy-six thousand, two hundred nine".