51665713774061 has 4 divisors (see below), whose sum is σ = 51680312736000. Its totient is φ = 51651114812124.

The previous prime is 51665713774019. The next prime is 51665713774187. The reversal of 51665713774061 is 16047731756615.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 51665713774061 - 2³⁰ = 51664640032237 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51665713774001) 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, 7299475661 + ... + 7299482738.

It is an arithmetic number, because the mean of its divisors is an integer number (12920078184000).

Almost surely, 2^{51665713774061} is an apocalyptic number.

It is an amenable number.

51665713774061 is a deficient number, since it is larger than the sum of its proper divisors (14598961939).

51665713774061 is a wasteful number, since it uses less digits than its factorization.

51665713774061 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14598961938.

The product of its (nonzero) digits is 22226400, while the sum is 59.

The spelling of 51665713774061 in words is "fifty-one trillion, six hundred sixty-five billion, seven hundred thirteen million, seven hundred seventy-four thousand, sixty-one".