166605051 has 4 divisors (see below), whose sum is σ = 222140072. Its totient is φ = 111070032.

The previous prime is 166605037. The next prime is 166605059. The reversal of 166605051 is 150506661.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 166605051 - 2¹⁹ = 166080763 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (166605059) 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 3 ways as a sum of consecutive naturals, for example, 27767506 + ... + 27767511.

It is an arithmetic number, because the mean of its divisors is an integer number (55535018).

Almost surely, 2^166605051 is an apocalyptic number.

166605051 is a deficient number, since it is larger than the sum of its proper divisors (55535021).

166605051 is an equidigital number, since it uses as much as digits as its factorization.

166605051 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55535020.

The product of its (nonzero) digits is 5400, while the sum is 30.

The square root of 166605051 is about 12907.5579022525. The cubic root of 166605051 is about 550.2533829740.

The spelling of 166605051 in words is "one hundred sixty-six million, six hundred five thousand, fifty-one".