166516505 has 8 divisors (see below), whose sum is σ = 201880392. Its totient is φ = 131839488.

The previous prime is 166516499. The next prime is 166516517. The reversal of 166516505 is 505615661.

It can be written as a sum of positive squares in 4 ways, for example, as 40246336 + 126270169 = 6344^2 + 11237^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 166516505 - 2⁸ = 166516249 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 171182 + ... + 172151.

It is an arithmetic number, because the mean of its divisors is an integer number (25235049).

Almost surely, 2^166516505 is an apocalyptic number.

It is an amenable number.

166516505 is a deficient number, since it is larger than the sum of its proper divisors (35363887).

166516505 is an equidigital number, since it uses as much as digits as its factorization.

166516505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 343435.

The product of its (nonzero) digits is 27000, while the sum is 35.

The square root of 166516505 is about 12904.1274404742. The cubic root of 166516505 is about 550.1558841889.

The spelling of 166516505 in words is "one hundred sixty-six million, five hundred sixteen thousand, five hundred five".