12749409 has 6 divisors (see below), whose sum is σ = 18415826. Its totient is φ = 8499600.

The previous prime is 12749393. The next prime is 12749413. The reversal of 12749409 is 90494721.

It can be written as a sum of positive squares in only one way, i.e., 7273809 + 5475600 = 2697^2 + 2340^2 .

It is not a de Polignac number, because 12749409 - 2⁴ = 12749393 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (12749449) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 708292 + ... + 708309.

Almost surely, 2^12749409 is an apocalyptic number.

It is an amenable number.

12749409 is a deficient number, since it is larger than the sum of its proper divisors (5666417).

12749409 is a wasteful number, since it uses less digits than its factorization.

12749409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1416607 (or 1416604 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 36.

The square root of 12749409 is about 3570.6314567594. The cubic root of 12749409 is about 233.6128267590.

The spelling of 12749409 in words is "twelve million, seven hundred forty-nine thousand, four hundred nine".