166057217 has 4 divisors (see below), whose sum is σ = 173277120. Its totient is φ = 158837316.

The previous prime is 166057193. The next prime is 166057237. The reversal of 166057217 is 712750661.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-166057217 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (166057237) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 3609917 + ... + 3609962.

It is an arithmetic number, because the mean of its divisors is an integer number (43319280).

Almost surely, 2^166057217 is an apocalyptic number.

It is an amenable number.

166057217 is a deficient number, since it is larger than the sum of its proper divisors (7219903).

166057217 is an equidigital number, since it uses as much as digits as its factorization.

166057217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7219902.

The product of its (nonzero) digits is 17640, while the sum is 35.

The square root of 166057217 is about 12886.3189856530. The cubic root of 166057217 is about 549.6496027095.

The spelling of 166057217 in words is "one hundred sixty-six million, fifty-seven thousand, two hundred seventeen".