12398891 has 4 divisors (see below), whose sum is σ = 12409800. Its totient is φ = 12387984.

The previous prime is 12398879. The next prime is 12398941. The reversal of 12398891 is 19889321.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 12398891 - 2²² = 8204587 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12398591) 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 3 ways as a sum of consecutive naturals, for example, 3521 + ... + 6098.

It is an arithmetic number, because the mean of its divisors is an integer number (3102450).

Almost surely, 2^12398891 is an apocalyptic number.

12398891 is a deficient number, since it is larger than the sum of its proper divisors (10909).

12398891 is an equidigital number, since it uses as much as digits as its factorization.

12398891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10908.

The product of its digits is 31104, while the sum is 41.

The square root of 12398891 is about 3521.2059013923. The cubic root of 12398891 is about 231.4520050338.

The spelling of 12398891 in words is "twelve million, three hundred ninety-eight thousand, eight hundred ninety-one".