166221280 has 48 divisors (see below), whose sum is σ = 393513120. Its totient is φ = 66350592.

The previous prime is 166221277. The next prime is 166221331. The reversal of 166221280 is 82122661.

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 7 ways as a sum of consecutive naturals, for example, 115606 + ... + 117034.

It is an arithmetic number, because the mean of its divisors is an integer number (8198190).

Almost surely, 2^166221280 is an apocalyptic number.

166221280 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

166221280 is an abundant number, since it is smaller than the sum of its proper divisors (227291840).

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

166221280 is a wasteful number, since it uses less digits than its factorization.

166221280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2171 (or 2163 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 28.

The square root of 166221280 is about 12892.6831962939. The cubic root of 166221280 is about 549.8305593754.

The spelling of 166221280 in words is "one hundred sixty-six million, two hundred twenty-one thousand, two hundred eighty".