166217909760 has 1920 divisors, whose sum is σ = 750701952000. Its totient is φ = 35115171840.

The previous prime is 166217909747. The next prime is 166217909797. The reversal of 166217909760 is 67909712661.

166217909760 is a `hidden beast` number, since 1 + 6 + 621 + 7 + 9 + 0 + 9 + 7 + 6 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (1920).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a junction number, because it is equal to n+sod(n) for n = 166217909697 and 166217909706.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 4054095340 + ... + 4054095380.

It is an arithmetic number, because the mean of its divisors is an integer number (390990600).

Almost surely, 2^166217909760 is an apocalyptic number.

166217909760 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 166217909760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (375350976000).

166217909760 is an abundant number, since it is smaller than the sum of its proper divisors (584484042240).

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

166217909760 is an frugal number, since it uses more digits than its factorization.

166217909760 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 119 (or 77 counting only the distinct ones).

The product of its (nonzero) digits is 1714608, while the sum is 54.

The spelling of 166217909760 in words is "one hundred sixty-six billion, two hundred seventeen million, nine hundred nine thousand, seven hundred sixty".