166389520 has 60 divisors (see below), whose sum is σ = 425246220. Its totient is φ = 60501760.

The previous prime is 166389469. The next prime is 166389527. The reversal of 166389520 is 25983661.

166389520 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 114318864 + 52070656 = 10692^2 + 7216^2 .

It is a Harshad number since it is a multiple of its sum of digits (40).

It is not an unprimeable number, because it can be changed into a prime (166389527) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1086 + ... + 18274.

It is an arithmetic number, because the mean of its divisors is an integer number (7087437).

Almost surely, 2^166389520 is an apocalyptic number.

166389520 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 166389520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (212623110).

166389520 is an abundant number, since it is smaller than the sum of its proper divisors (258856700).

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

166389520 is a wasteful number, since it uses less digits than its factorization.

166389520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17224 (or 17207 counting only the distinct ones).

The product of its (nonzero) digits is 77760, while the sum is 40.

The square root of 166389520 is about 12899.2061771258. The cubic root of 166389520 is about 550.0159995346.

The spelling of 166389520 in words is "one hundred sixty-six million, three hundred eighty-nine thousand, five hundred twenty".