166556500 has 72 divisors (see below), whose sum is σ = 399979944. Its totient is φ = 60544000.

The previous prime is 166556431. The next prime is 166556513. The reversal of 166556500 is 5655661.

It can be written as a sum of positive squares in 4 ways, for example, as 352836 + 166203664 = 594^2 + 12892^2 .

It is a congruent number.

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, 59124 + ... + 61876.

It is an arithmetic number, because the mean of its divisors is an integer number (5555277).

Almost surely, 2^166556500 is an apocalyptic number.

166556500 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 166556500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (199989972).

166556500 is an abundant number, since it is smaller than the sum of its proper divisors (233423444).

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

166556500 is a wasteful number, since it uses less digits than its factorization.

166556500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2794 (or 2771 counting only the distinct ones).

The product of its (nonzero) digits is 27000, while the sum is 34.

The square root of 166556500 is about 12905.6770453936. The cubic root of 166556500 is about 550.1999273168.

The spelling of 166556500 in words is "one hundred sixty-six million, five hundred fifty-six thousand, five hundred".