166056661 has 2 divisors, whose sum is σ = 166056662. Its totient is φ = 166056660.

The previous prime is 166056647. The next prime is 166056673. The reversal of 166056661 is 166650661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 155127025 + 10929636 = 12455^2 + 3306^2 .

It is a cyclic number.

It is not a de Polignac number, because 166056661 - 2⁷ = 166056533 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 166056661.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (166053661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83028330 + 83028331.

It is an arithmetic number, because the mean of its divisors is an integer number (83028331).

Almost surely, 2^166056661 is an apocalyptic number.

It is an amenable number.

166056661 is a deficient number, since it is larger than the sum of its proper divisors (1).

166056661 is an equidigital number, since it uses as much as digits as its factorization.

166056661 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 38880, while the sum is 37.

The square root of 166056661 is about 12886.2974123679. The cubic root of 166056661 is about 549.6489892553.

The spelling of 166056661 in words is "one hundred sixty-six million, fifty-six thousand, six hundred sixty-one".