566001661 has 4 divisors (see below), whose sum is σ = 569128924. Its totient is φ = 562874400.

The previous prime is 566001649. The next prime is 566001701. The reversal of 566001661 is 166100665.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 166100665 = 5 ⋅33220133.

It can be written as a sum of positive squares in 2 ways, for example, as 96412761 + 469588900 = 9819^2 + 21670^2 .

It is a cyclic number.

It is not a de Polignac number, because 566001661 - 2⁵ = 566001629 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (566001061) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1563360 + ... + 1563721.

It is an arithmetic number, because the mean of its divisors is an integer number (142282231).

Almost surely, 2^566001661 is an apocalyptic number.

It is an amenable number.

566001661 is a deficient number, since it is larger than the sum of its proper divisors (3127263).

566001661 is a wasteful number, since it uses less digits than its factorization.

566001661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3127262.

The product of its (nonzero) digits is 6480, while the sum is 31.

The square root of 566001661 is about 23790.7894152338. The cubic root of 566001661 is about 827.1911929945.

The spelling of 566001661 in words is "five hundred sixty-six million, one thousand, six hundred sixty-one".