12172509 has 12 divisors (see below), whose sum is σ = 17659200. Its totient is φ = 8079624.

The previous prime is 12172487. The next prime is 12172513. The reversal of 12172509 is 90527121.

It is not a de Polignac number, because 12172509 - 2⁵ = 12172477 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12172549) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 679 + ... + 4980.

It is an arithmetic number, because the mean of its divisors is an integer number (1471600).

Almost surely, 2^12172509 is an apocalyptic number.

It is an amenable number.

12172509 is a deficient number, since it is larger than the sum of its proper divisors (5486691).

12172509 is a wasteful number, since it uses less digits than its factorization.

12172509 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5904 (or 5901 counting only the distinct ones).

The product of its (nonzero) digits is 1260, while the sum is 27.

The square root of 12172509 is about 3488.9122946844. The cubic root of 12172509 is about 230.0347080577.

The spelling of 12172509 in words is "twelve million, one hundred seventy-two thousand, five hundred nine".