165666656515101 has 8 divisors (see below), whose sum is σ = 252444428975424. Its totient is φ = 94666660865760.

The previous prime is 165666656515051. The next prime is 165666656515127. The reversal of 165666656515101 is 101515656666561.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 165666656515101 - 2²⁵ = 165666622960669 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165666656515141) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3944444202720 + ... + 3944444202761.

It is an arithmetic number, because the mean of its divisors is an integer number (31555553621928).

Almost surely, 2^{165666656515101} is an apocalyptic number.

It is an amenable number.

165666656515101 is a deficient number, since it is larger than the sum of its proper divisors (86777772460323).

165666656515101 is an equidigital number, since it uses as much as digits as its factorization.

165666656515101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7888888405491.

The product of its (nonzero) digits is 29160000, while the sum is 60.

The spelling of 165666656515101 in words is "one hundred sixty-five trillion, six hundred sixty-six billion, six hundred fifty-six million, five hundred fifteen thousand, one hundred one".