12915991809 has 40 divisors (see below), whose sum is σ = 22062361728. Its totient is φ = 7376624640.

The previous prime is 12915991763. The next prime is 12915991843. The reversal of 12915991809 is 90819951921.

It is not a de Polignac number, because 12915991809 - 2³³ = 4326057217 is a prime.

It is not an unprimeable number, because it can be changed into a prime (12916991809) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 1305409 + ... + 1315265.

Almost surely, 2^12915991809 is an apocalyptic number.

It is an amenable number.

12915991809 is a deficient number, since it is larger than the sum of its proper divisors (9146369919).

12915991809 is an equidigital number, since it uses as much as digits as its factorization.

12915991809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12187 (or 12178 counting only the distinct ones).

The product of its (nonzero) digits is 524880, while the sum is 54.

The spelling of 12915991809 in words is "twelve billion, nine hundred fifteen million, nine hundred ninety-one thousand, eight hundred nine".