166606523 has 4 divisors (see below), whose sum is σ = 171109440. Its totient is φ = 162103608.

The previous prime is 166606519. The next prime is 166606589. The reversal of 166606523 is 325606661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 325606661 = 17 ⋅19153333.

It is a cyclic number.

It is not a de Polignac number, because 166606523 - 2² = 166606519 is a prime.

It is a super-3 number, since 3×166606523³ (a number of 26 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (166602523) 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, 2251403 + ... + 2251476.

It is an arithmetic number, because the mean of its divisors is an integer number (42777360).

Almost surely, 2^166606523 is an apocalyptic number.

166606523 is a deficient number, since it is larger than the sum of its proper divisors (4502917).

166606523 is an equidigital number, since it uses as much as digits as its factorization.

166606523 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4502916.

The product of its (nonzero) digits is 38880, while the sum is 35.

The square root of 166606523 is about 12907.6149229825. The cubic root of 166606523 is about 550.2550035143.

The spelling of 166606523 in words is "one hundred sixty-six million, six hundred six thousand, five hundred twenty-three".