166557211 has 16 divisors (see below), whose sum is σ = 190179360. Its totient is φ = 144875520.

The previous prime is 166557197. The next prime is 166557227. The reversal of 166557211 is 112755661.

It is a cyclic number.

It is not a de Polignac number, because 166557211 - 2¹⁵ = 166524443 is a prime.

It is not an unprimeable number, because it can be changed into a prime (166557271) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6955 + ... + 19531.

It is an arithmetic number, because the mean of its divisors is an integer number (11886210).

Almost surely, 2^166557211 is an apocalyptic number.

166557211 is a deficient number, since it is larger than the sum of its proper divisors (23622149).

166557211 is a wasteful number, since it uses less digits than its factorization.

166557211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12654.

The product of its digits is 12600, while the sum is 34.

The square root of 166557211 is about 12905.7045913813. The cubic root of 166557211 is about 550.2007102175.

The spelling of 166557211 in words is "one hundred sixty-six million, five hundred fifty-seven thousand, two hundred eleven".