12666637 has 4 divisors (see below), whose sum is σ = 12711996. Its totient is φ = 12621280.

The previous prime is 12666607. The next prime is 12666671. The reversal of 12666637 is 73666621.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 7918596 + 4748041 = 2814^2 + 2179^2 .

It is a cyclic number.

It is not a de Polignac number, because 12666637 - 2¹⁵ = 12633869 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12666596 and 12666605.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12666607) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22258 + ... + 22819.

It is an arithmetic number, because the mean of its divisors is an integer number (3177999).

Almost surely, 2^12666637 is an apocalyptic number.

It is an amenable number.

12666637 is a deficient number, since it is larger than the sum of its proper divisors (45359).

12666637 is an equidigital number, since it uses as much as digits as its factorization.

12666637 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45358.

The product of its digits is 54432, while the sum is 37.

The square root of 12666637 is about 3559.0219162011. The cubic root of 12666637 is about 233.1061732527.

The spelling of 12666637 in words is "twelve million, six hundred sixty-six thousand, six hundred thirty-seven".