166851868539 has 16 divisors (see below), whose sum is σ = 226712227104. Its totient is φ = 109113888000.

The previous prime is 166851868523. The next prime is 166851868553. The reversal of 166851868539 is 935868158661.

It is not a de Polignac number, because 166851868539 - 2⁴ = 166851868523 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 166851868539.

It is not an unprimeable number, because it can be changed into a prime (166851868639) 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 15 ways as a sum of consecutive naturals, for example, 708199 + ... + 913919.

It is an arithmetic number, because the mean of its divisors is an integer number (14169514194).

Almost surely, 2^166851868539 is an apocalyptic number.

166851868539 is a deficient number, since it is larger than the sum of its proper divisors (59860358565).

166851868539 is a wasteful number, since it uses less digits than its factorization.

166851868539 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 210878.

The product of its digits is 74649600, while the sum is 66.

The spelling of 166851868539 in words is "one hundred sixty-six billion, eight hundred fifty-one million, eight hundred sixty-eight thousand, five hundred thirty-nine".