166641720 has 128 divisors (see below), whose sum is σ = 574179840. Its totient is φ = 37900800.

The previous prime is 166641719. The next prime is 166641751. The reversal of 166641720 is 27146661.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 237370 + ... + 238070.

It is an arithmetic number, because the mean of its divisors is an integer number (4485780).

Almost surely, 2^166641720 is an apocalyptic number.

166641720 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 166641720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (287089920).

166641720 is an abundant number, since it is smaller than the sum of its proper divisors (407538120).

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

166641720 is a wasteful number, since it uses less digits than its factorization.

166641720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1005 (or 1001 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 33.

The square root of 166641720 is about 12908.9782709555. The cubic root of 166641720 is about 550.2937494196.

The spelling of 166641720 in words is "one hundred sixty-six million, six hundred forty-one thousand, seven hundred twenty".