166516222 has 4 divisors (see below), whose sum is σ = 249774336. Its totient is φ = 83258110.

The previous prime is 166516219. The next prime is 166516223. The reversal of 166516222 is 222615661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 222615661 = 9343 ⋅23827.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166516223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41629054 + ... + 41629057.

It is an arithmetic number, because the mean of its divisors is an integer number (62443584).

Almost surely, 2^166516222 is an apocalyptic number.

166516222 is a deficient number, since it is larger than the sum of its proper divisors (83258114).

166516222 is an equidigital number, since it uses as much as digits as its factorization.

166516222 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83258113.

The product of its digits is 8640, while the sum is 31.

The square root of 166516222 is about 12904.1164749858. The cubic root of 166516222 is about 550.1555725197.

The spelling of 166516222 in words is "one hundred sixty-six million, five hundred sixteen thousand, two hundred twenty-two".