566501661 has 64 divisors (see below), whose sum is σ = 964362240. Its totient is φ = 325321920.

The previous prime is 566501629. The next prime is 566501711. The reversal of 566501661 is 166105665.

It is not a de Polignac number, because 566501661 - 2⁵ = 566501629 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (566501861) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 867211 + ... + 867863.

It is an arithmetic number, because the mean of its divisors is an integer number (15068160).

Almost surely, 2^566501661 is an apocalyptic number.

It is an amenable number.

566501661 is a deficient number, since it is larger than the sum of its proper divisors (397860579).

566501661 is a wasteful number, since it uses less digits than its factorization.

566501661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 823 (or 817 counting only the distinct ones).

The product of its (nonzero) digits is 32400, while the sum is 36.

The square root of 566501661 is about 23801.2953639082. The cubic root of 566501661 is about 827.4346986801.

It can be divided in two parts, 56650 and 1661, that added together give a triangular number (58311 = T₃₄₁).

The spelling of 566501661 in words is "five hundred sixty-six million, five hundred one thousand, six hundred sixty-one".