166686871559856 has 120 divisors (see below), whose sum is σ = 436813127503872. Its totient is φ = 54772817769600.

The previous prime is 166686871559809. The next prime is 166686871559909. The reversal of 166686871559856 is 658955178686661.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2136780405 + ... + 2136858411.

Almost surely, 2^{166686871559856} is an apocalyptic number.

166686871559856 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 166686871559856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (218406563751936).

166686871559856 is an abundant number, since it is smaller than the sum of its proper divisors (270126255944016).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

166686871559856 is an equidigital number, since it uses as much as digits as its factorization.

166686871559856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 86991 (or 86914 counting only the distinct ones).

The product of its digits is 31352832000, while the sum is 87.

The spelling of 166686871559856 in words is "one hundred sixty-six trillion, six hundred eighty-six billion, eight hundred seventy-one million, five hundred fifty-nine thousand, eight hundred fifty-six".