12738991 has 2 divisors, whose sum is σ = 12738992. Its totient is φ = 12738990.

The previous prime is 12738983. The next prime is 12738997. The reversal of 12738991 is 19983721.

12738991 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 12738991 - 2³ = 12738983 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12738997) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6369495 + 6369496.

It is an arithmetic number, because the mean of its divisors is an integer number (6369496).

Almost surely, 2^12738991 is an apocalyptic number.

12738991 is a deficient number, since it is larger than the sum of its proper divisors (1).

12738991 is an equidigital number, since it uses as much as digits as its factorization.

12738991 is an evil number, because the sum of its binary digits is even.

The product of its digits is 27216, while the sum is 40.

The square root of 12738991 is about 3569.1723130160. The cubic root of 12738991 is about 233.5491782757.

The spelling of 12738991 in words is "twelve million, seven hundred thirty-eight thousand, nine hundred ninety-one".