12517717666 has 4 divisors (see below), whose sum is σ = 18776576502. Its totient is φ = 6258858832.

The previous prime is 12517717637. The next prime is 12517717679. The reversal of 12517717666 is 66671771521.

12517717666 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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., 12288831025 + 228886641 = 110855^2 + 15129^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3129429415 + ... + 3129429418.

Almost surely, 2^12517717666 is an apocalyptic number.

12517717666 is a deficient number, since it is larger than the sum of its proper divisors (6258858836).

12517717666 is an equidigital number, since it uses as much as digits as its factorization.

12517717666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6258858835.

The product of its digits is 740880, while the sum is 49.

The spelling of 12517717666 in words is "twelve billion, five hundred seventeen million, seven hundred seventeen thousand, six hundred sixty-six".