166720000 has 100 divisors (see below), whose sum is σ = 417058686. Its totient is φ = 66560000.

The previous prime is 166719997. The next prime is 166720007. The reversal of 166720000 is 27661.

166720000 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 5 ways, for example, as 256 + 166719744 = 16^2 + 12912^2 .

It is a tau number, because it is divible by the number of its divisors (100).

It is not an unprimeable number, because it can be changed into a prime (166720007) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 319740 + ... + 320260.

Almost surely, 2^166720000 is an apocalyptic number.

166720000 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 166720000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (208529343).

166720000 is an abundant number, since it is smaller than the sum of its proper divisors (250338686).

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

166720000 is an frugal number, since it uses more digits than its factorization.

166720000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 559 (or 528 counting only the distinct ones).

The product of its (nonzero) digits is 504, while the sum is 22.

The square root of 166720000 is about 12912.0099132552. The cubic root of 166720000 is about 550.3799028177.

Adding to 166720000 its reverse (27661), we get a palindrome (166747661).

The spelling of 166720000 in words is "one hundred sixty-six million, seven hundred twenty thousand".