166657720320 has 1632 divisors, whose sum is σ = 769464364032. Its totient is φ = 33634123776.

The previous prime is 166657720319. The next prime is 166657720331. The reversal of 166657720320 is 23027756661.

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

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 7245987829 + ... + 7245987851.

Almost surely, 2^166657720320 is an apocalyptic number.

166657720320 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 166657720320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (384732182016).

166657720320 is an abundant number, since it is smaller than the sum of its proper divisors (602806643712).

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

166657720320 is an frugal number, since it uses more digits than its factorization.

166657720320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95 (or 53 counting only the distinct ones).

The product of its (nonzero) digits is 635040, while the sum is 45.

The spelling of 166657720320 in words is "one hundred sixty-six billion, six hundred fifty-seven million, seven hundred twenty thousand, three hundred twenty".