165666650550061 has 16 divisors (see below), whose sum is σ = 169320609057600. Its totient is φ = 162058310013568.

The previous prime is 165666650550059. The next prime is 165666650550173. The reversal of 165666650550061 is 160055056666561.

It is a cyclic number.

It is not a de Polignac number, because 165666650550061 - 2¹ = 165666650550059 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 165666650549978 and 165666650550005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165666650550001) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14303191 + ... + 23149828.

It is an arithmetic number, because the mean of its divisors is an integer number (10582538066100).

Almost surely, 2^{165666650550061} is an apocalyptic number.

It is an amenable number.

165666650550061 is a deficient number, since it is larger than the sum of its proper divisors (3653958507539).

165666650550061 is a wasteful number, since it uses less digits than its factorization.

165666650550061 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37453628.

The product of its (nonzero) digits is 29160000, while the sum is 58.

The spelling of 165666650550061 in words is "one hundred sixty-five trillion, six hundred sixty-six billion, six hundred fifty million, five hundred fifty thousand, sixty-one".