12938409 has 27 divisors (see below), whose sum is σ = 20732439. Its totient is φ = 7769520.

The previous prime is 12938389. The next prime is 12938461. The reversal of 12938409 is 90483921.

The square root of 12938409 is 3597.

It is a perfect power (a square), and thus also a powerful number.

12938409 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 9018009 + 3920400 = 3003^2 + 1980^2 .

It is not a de Polignac number, because 12938409 - 2⁷ = 12938281 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (12938209) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 118647 + ... + 118755.

Almost surely, 2^12938409 is an apocalyptic number.

12938409 is the 3597-th square number.

12938409 is the 1799-th centered octagonal number.

It is an amenable number.

12938409 is a deficient number, since it is larger than the sum of its proper divisors (7794030).

12938409 is a wasteful number, since it uses less digits than its factorization.

12938409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 246 (or 123 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 36.

The cubic root of 12938409 is about 234.7615447510.

Multiplying 12938409 by its sum of digits (36), we get a square (465782724 = 21582²).

The spelling of 12938409 in words is "twelve million, nine hundred thirty-eight thousand, four hundred nine".