166561834 has 4 divisors (see below), whose sum is σ = 249842754. Its totient is φ = 83280916.

The previous prime is 166561831. The next prime is 166561859. The reversal of 166561834 is 438165661.

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

It can be written as a sum of positive squares in only one way, i.e., 118744609 + 47817225 = 10897^2 + 6915^2 .

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (166561831) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41640457 + ... + 41640460.

Almost surely, 2^166561834 is an apocalyptic number.

166561834 is a deficient number, since it is larger than the sum of its proper divisors (83280920).

166561834 is an equidigital number, since it uses as much as digits as its factorization.

166561834 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83280919.

The product of its digits is 103680, while the sum is 40.

The square root of 166561834 is about 12905.8836969810. The cubic root of 166561834 is about 550.2058006692.

The spelling of 166561834 in words is "one hundred sixty-six million, five hundred sixty-one thousand, eight hundred thirty-four".