51550166665081 has 4 divisors (see below), whose sum is σ = 58914476188672. Its totient is φ = 44185857141492.

The previous prime is 51550166665031. The next prime is 51550166665097. The reversal of 51550166665081 is 18056666105515.

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 51550166665081 - 2¹⁵ = 51550166632313 is a prime.

It is a super-2 number, since 2×51550166665081² (a number of 28 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51550166665031) 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, 3682154761785 + ... + 3682154761798.

It is an arithmetic number, because the mean of its divisors is an integer number (14728619047168).

Almost surely, 2^{51550166665081} is an apocalyptic number.

It is an amenable number.

51550166665081 is a deficient number, since it is larger than the sum of its proper divisors (7364309523591).

51550166665081 is an equidigital number, since it uses as much as digits as its factorization.

51550166665081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7364309523590.

The product of its (nonzero) digits is 6480000, while the sum is 55.

The spelling of 51550166665081 in words is "fifty-one trillion, five hundred fifty billion, one hundred sixty-six million, six hundred sixty-five thousand, eighty-one".