12781689 has 12 divisors (see below), whose sum is σ = 17243184. Its totient is φ = 8421664.

The previous prime is 12781669. The next prime is 12781723. The reversal of 12781689 is 98618721.

It is not a de Polignac number, because 12781689 - 2²¹ = 10684537 is a prime.

Its product of digits (48384) is a multiple of the sum of its prime factors (504).

It is a self number, because there is not a number n which added to its sum of digits gives 12781689.

It is not an unprimeable number, because it can be changed into a prime (12781609) 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, 56194 + ... + 56420.

It is an arithmetic number, because the mean of its divisors is an integer number (1436932).

Almost surely, 2^12781689 is an apocalyptic number.

It is an amenable number.

12781689 is a deficient number, since it is larger than the sum of its proper divisors (4461495).

12781689 is an equidigital number, since it uses as much as digits as its factorization.

12781689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 504 (or 367 counting only the distinct ones).

The product of its digits is 48384, while the sum is 42.

The square root of 12781689 is about 3575.1488080918. The cubic root of 12781689 is about 233.8098206395.

The spelling of 12781689 in words is "twelve million, seven hundred eighty-one thousand, six hundred eighty-nine".