12606799666 has 4 divisors (see below), whose sum is σ = 18910199502. Its totient is φ = 6303399832.

The previous prime is 12606799631. The next prime is 12606799741. The reversal of 12606799666 is 66699760621.

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

It can be written as a sum of positive squares in only one way, i.e., 12231254025 + 375545641 = 110595^2 + 19379^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 12606799666.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3151699915 + ... + 3151699918.

Almost surely, 2^12606799666 is an apocalyptic number.

12606799666 is a deficient number, since it is larger than the sum of its proper divisors (6303399836).

12606799666 is an equidigital number, since it uses as much as digits as its factorization.

12606799666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6303399835.

The product of its (nonzero) digits is 8817984, while the sum is 58.

The spelling of 12606799666 in words is "twelve billion, six hundred six million, seven hundred ninety-nine thousand, six hundred sixty-six".