12639775 has 12 divisors (see below), whose sum is σ = 15896304. Its totient is φ = 9968000.

The previous prime is 12639713. The next prime is 12639791. The reversal of 12639775 is 57793621.

It is not a de Polignac number, because 12639775 - 2¹¹ = 12637727 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1786 + ... + 5335.

It is an arithmetic number, because the mean of its divisors is an integer number (1324692).

Almost surely, 2^12639775 is an apocalyptic number.

12639775 is a deficient number, since it is larger than the sum of its proper divisors (3256529).

12639775 is an equidigital number, since it uses as much as digits as its factorization.

12639775 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7202 (or 7197 counting only the distinct ones).

The product of its digits is 79380, while the sum is 40.

The square root of 12639775 is about 3555.2461236882. The cubic root of 12639775 is about 232.9412747186.

The spelling of 12639775 in words is "twelve million, six hundred thirty-nine thousand, seven hundred seventy-five".