12918491 has 2 divisors, whose sum is σ = 12918492. Its totient is φ = 12918490.

The previous prime is 12918481. The next prime is 12918497. The reversal of 12918491 is 19481921.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12918491 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (12918497) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6459245 + 6459246.

It is an arithmetic number, because the mean of its divisors is an integer number (6459246).

Almost surely, 2^12918491 is an apocalyptic number.

12918491 is a deficient number, since it is larger than the sum of its proper divisors (1).

12918491 is an equidigital number, since it uses as much as digits as its factorization.

12918491 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5184, while the sum is 35.

The square root of 12918491 is about 3594.2302374778. The cubic root of 12918491 is about 234.6410151975.

The spelling of 12918491 in words is "twelve million, nine hundred eighteen thousand, four hundred ninety-one".