166177920 has 128 divisors (see below), whose sum is σ = 542868480. Its totient is φ = 43212800.

The previous prime is 166177909. The next prime is 166177931. The reversal of 166177920 is 29771661.

It is an interprime number because it is at equal distance from previous prime (166177909) and next prime (166177931).

It is a tau number, because it is divible by the number of its divisors (128).

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 15 ways as a sum of consecutive naturals, for example, 77665 + ... + 79775.

It is an arithmetic number, because the mean of its divisors is an integer number (4241160).

Almost surely, 2^166177920 is an apocalyptic number.

166177920 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 166177920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (271434240).

166177920 is an abundant number, since it is smaller than the sum of its proper divisors (376690560).

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

166177920 is a wasteful number, since it uses less digits than its factorization.

166177920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2174 (or 2162 counting only the distinct ones).

The product of its (nonzero) digits is 31752, while the sum is 39.

The square root of 166177920 is about 12891.0015126832. The cubic root of 166177920 is about 549.7827461504.

Subtracting from 166177920 its sum of digits (39), we obtain a square (166177881 = 12891²).

The spelling of 166177920 in words is "one hundred sixty-six million, one hundred seventy-seven thousand, nine hundred twenty".