12731609 has 16 divisors (see below), whose sum is σ = 14541120. Its totient is φ = 11040960.

The previous prime is 12731599. The next prime is 12731611. The reversal of 12731609 is 90613721.

It is a cyclic number.

It is not a de Polignac number, because 12731609 - 2¹² = 12727513 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (29).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (12731629) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 33947 + ... + 34319.

It is an arithmetic number, because the mean of its divisors is an integer number (908820).

Almost surely, 2^12731609 is an apocalyptic number.

It is an amenable number.

12731609 is a deficient number, since it is larger than the sum of its proper divisors (1809511).

12731609 is a wasteful number, since it uses less digits than its factorization.

12731609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 520.

The product of its (nonzero) digits is 2268, while the sum is 29.

The square root of 12731609 is about 3568.1380298413. The cubic root of 12731609 is about 233.5040571416.

It can be divided in two parts, 1273 and 1609, that added together give a palindrome (2882).

The spelling of 12731609 in words is "twelve million, seven hundred thirty-one thousand, six hundred nine".