51666692747 has 4 divisors (see below), whose sum is σ = 51675004176. Its totient is φ = 51658381320.

The previous prime is 51666692711. The next prime is 51666692789. The reversal of 51666692747 is 74729666615.

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

It is a cyclic number.

It is not a de Polignac number, because 51666692747 - 2²⁰ = 51665644171 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51666692797) 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, 4146383 + ... + 4158824.

It is an arithmetic number, because the mean of its divisors is an integer number (12918751044).

Almost surely, 2^51666692747 is an apocalyptic number.

51666692747 is a deficient number, since it is larger than the sum of its proper divisors (8311429).

51666692747 is an equidigital number, since it uses as much as digits as its factorization.

51666692747 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8311428.

The product of its digits is 22861440, while the sum is 59.

The spelling of 51666692747 in words is "fifty-one billion, six hundred sixty-six million, six hundred ninety-two thousand, seven hundred forty-seven".