166851868685 has 8 divisors (see below), whose sum is σ = 212000021496.
Its totient is φ = 125629642240.
The previous prime is 166851868657. The next prime is 166851868691. The reversal of 166851868685 is 586868158661.
It can be written as a sum of positive squares in 4 ways, for example, as 15939820009 + 150912048676 = 126253^2 + 388474^2
It is a sphenic number, since it is the product of 3 distinct primes.
It is not a de Polignac number, because 166851868685 - 212 = 166851864589 is a prime.
It is a Duffinian number.
It is a congruent number.
It is an unprimeable number.
It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 981481496 + ... + 981481665.
It is an arithmetic number, because the mean of its divisors is an integer number (26500002687).
Almost surely, 2166851868685 is an apocalyptic number.
It is an amenable number.
166851868685 is a deficient number, since it is larger than the sum of its proper divisors (45148152811).
166851868685 is a wasteful number, since it uses less digits than its factorization.
166851868685 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 1962963183.
The product of its digits is 132710400, while the sum is 68.
The spelling of 166851868685 in words is "one hundred sixty-six billion, eight hundred fifty-one million, eight hundred sixty-eight thousand, six hundred eighty-five".