166605223 has 4 divisors (see below), whose sum is σ = 166696048. Its totient is φ = 166514400.

The previous prime is 166605217. The next prime is 166605239. The reversal of 166605223 is 322506661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 322506661 = 3989 ⋅80849.

It is a cyclic number.

It is not a de Polignac number, because 166605223 - 2¹³ = 166597031 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166608223) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 42603 + ... + 46348.

It is an arithmetic number, because the mean of its divisors is an integer number (41674012).

Almost surely, 2^166605223 is an apocalyptic number.

166605223 is a deficient number, since it is larger than the sum of its proper divisors (90825).

166605223 is an equidigital number, since it uses as much as digits as its factorization.

166605223 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90824.

The product of its (nonzero) digits is 12960, while the sum is 31.

The square root of 166605223 is about 12907.5645650138. The cubic root of 166605223 is about 550.2535723311.

The spelling of 166605223 in words is "one hundred sixty-six million, six hundred five thousand, two hundred twenty-three".