1312240399 has 2 divisors, whose sum is σ = 1312240400. Its totient is φ = 1312240398.

The previous prime is 1312240381. The next prime is 1312240441. The reversal of 1312240399 is 9930422131.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1312240399 - 2¹¹ = 1312238351 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1312240309) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 656120199 + 656120200.

It is an arithmetic number, because the mean of its divisors is an integer number (656120200).

Almost surely, 2^1312240399 is an apocalyptic number.

1312240399 is a deficient number, since it is larger than the sum of its proper divisors (1).

1312240399 is an equidigital number, since it uses as much as digits as its factorization.

1312240399 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 11664, while the sum is 34.

The square root of 1312240399 is about 36224.8588541074. The cubic root of 1312240399 is about 1094.8075943361.

The spelling of 1312240399 in words is "one billion, three hundred twelve million, two hundred forty thousand, three hundred ninety-nine".