51666266615 has 4 divisors (see below), whose sum is σ = 61999519944. Its totient is φ = 41333013288.

The previous prime is 51666266611. The next prime is 51666266623.

51666266615 is nontrivially palindromic in base 10.

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 51666266615 - 2² = 51666266611 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51666266611) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5166626657 + ... + 5166626666.

It is an arithmetic number, because the mean of its divisors is an integer number (15499879986).

Almost surely, 2^51666266615 is an apocalyptic number.

51666266615 is a deficient number, since it is larger than the sum of its proper divisors (10333253329).

51666266615 is a wasteful number, since it uses less digits than its factorization.

51666266615 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10333253328.

The product of its digits is 2332800, while the sum is 50.

The spelling of 51666266615 in words is "fifty-one billion, six hundred sixty-six million, two hundred sixty-six thousand, six hundred fifteen".