166042661 has 16 divisors (see below), whose sum is σ = 178461360. Its totient is φ = 154183680.

The previous prime is 166042649. The next prime is 166042663. The reversal of 166042661 is 166240661.

166042661 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 8 ways, for example, as 122500 + 165920161 = 350^2 + 12881^2 .

It is a cyclic number.

It is not a de Polignac number, because 166042661 - 2¹⁴ = 166026277 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166042663) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 85841 + ... + 87753.

It is an arithmetic number, because the mean of its divisors is an integer number (11153835).

Almost surely, 2^166042661 is an apocalyptic number.

It is an amenable number.

166042661 is a deficient number, since it is larger than the sum of its proper divisors (12418699).

166042661 is a wasteful number, since it uses less digits than its factorization.

166042661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2056.

The product of its (nonzero) digits is 10368, while the sum is 32.

The square root of 166042661 is about 12885.7541882499. The cubic root of 166042661 is about 549.6335421140.

The spelling of 166042661 in words is "one hundred sixty-six million, forty-two thousand, six hundred sixty-one".