13239749 has 2 divisors, whose sum is σ = 13239750. Its totient is φ = 13239748.

The previous prime is 13239731. The next prime is 13239757. The reversal of 13239749 is 94793231.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12888100 + 351649 = 3590^2 + 593^2 .

It is a cyclic number.

It is not a de Polignac number, because 13239749 - 2⁸ = 13239493 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13239649) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6619874 + 6619875.

It is an arithmetic number, because the mean of its divisors is an integer number (6619875).

Almost surely, 2^13239749 is an apocalyptic number.

It is an amenable number.

13239749 is a deficient number, since it is larger than the sum of its proper divisors (1).

13239749 is an equidigital number, since it uses as much as digits as its factorization.

13239749 is an evil number, because the sum of its binary digits is even.

The product of its digits is 40824, while the sum is 38.

The square root of 13239749 is about 3638.6465890493. The cubic root of 13239749 is about 236.5701347595.

The spelling of 13239749 in words is "thirteen million, two hundred thirty-nine thousand, seven hundred forty-nine".