1312131409 has 2 divisors, whose sum is σ = 1312131410. Its totient is φ = 1312131408.

The previous prime is 1312131377. The next prime is 1312131433. The reversal of 1312131409 is 9041312131.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1276990225 + 35141184 = 35735^2 + 5928^2 .

It is a cyclic number.

It is not a de Polignac number, because 1312131409 - 2⁵ = 1312131377 is a prime.

It is not a weakly prime, because it can be changed into another prime (1312101409) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 656065704 + 656065705.

It is an arithmetic number, because the mean of its divisors is an integer number (656065705).

Almost surely, 2^1312131409 is an apocalyptic number.

It is an amenable number.

1312131409 is a deficient number, since it is larger than the sum of its proper divisors (1).

1312131409 is an equidigital number, since it uses as much as digits as its factorization.

1312131409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 648, while the sum is 25.

The square root of 1312131409 is about 36223.3544691819. The cubic root of 1312131409 is about 1094.7772832276. Note that the first 3 decimals are identical.

The spelling of 1312131409 in words is "one billion, three hundred twelve million, one hundred thirty-one thousand, four hundred nine".