12899991 has 16 divisors (see below), whose sum is σ = 19613664. Its totient is φ = 7471104.

The previous prime is 12899977. The next prime is 12900001. The reversal of 12899991 is 19999821.

It is not a de Polignac number, because 12899991 - 2⁵ = 12899959 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 12899991.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12899951) 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 15 ways as a sum of consecutive naturals, for example, 9066 + ... + 10391.

It is an arithmetic number, because the mean of its divisors is an integer number (1225854).

Almost surely, 2^12899991 is an apocalyptic number.

12899991 is a deficient number, since it is larger than the sum of its proper divisors (6713673).

12899991 is a wasteful number, since it uses less digits than its factorization.

12899991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19490.

The product of its digits is 104976, while the sum is 48.

The square root of 12899991 is about 3591.6557463098. The cubic root of 12899991 is about 234.5289553460.

The spelling of 12899991 in words is "twelve million, eight hundred ninety-nine thousand, nine hundred ninety-one".