12489991 has 2 divisors, whose sum is σ = 12489992. Its totient is φ = 12489990.

The previous prime is 12489959. The next prime is 12490001. The reversal of 12489991 is 19998421.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 12489991 - 2⁵ = 12489959 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12489941) 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 as a sum of consecutive naturals, namely, 6244995 + 6244996.

It is an arithmetic number, because the mean of its divisors is an integer number (6244996).

Almost surely, 2^12489991 is an apocalyptic number.

12489991 is a deficient number, since it is larger than the sum of its proper divisors (1).

12489991 is an equidigital number, since it uses as much as digits as its factorization.

12489991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 46656, while the sum is 43.

The square root of 12489991 is about 3534.1181361126. The cubic root of 12489991 is about 232.0174815900.

The spelling of 12489991 in words is "twelve million, four hundred eighty-nine thousand, nine hundred ninety-one".