166266172800 has 2880 divisors, whose sum is σ = 824354269200. Its totient is φ = 32606945280.

The previous prime is 166266172769. The next prime is 166266172811. The reversal of 166266172800 is 8271662661.

166266172800 is a `hidden beast` number, since 1 + 6 + 6 + 2 + 6 + 617 + 28 + 0 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (2880).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 359 ways as a sum of consecutive naturals, for example, 3137097574 + ... + 3137097626.

Almost surely, 2^166266172800 is an apocalyptic number.

166266172800 is a gapful number since it is divisible by the number (10) 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 166266172800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (412177134600).

166266172800 is an abundant number, since it is smaller than the sum of its proper divisors (658088096400).

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

166266172800 is a wasteful number, since it uses less digits than its factorization.

166266172800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 135 (or 102 counting only the distinct ones).

The product of its (nonzero) digits is 290304, while the sum is 45.

The spelling of 166266172800 in words is "one hundred sixty-six billion, two hundred sixty-six million, one hundred seventy-two thousand, eight hundred".