561166601 has 4 divisors (see below), whose sum is σ = 561248772. Its totient is φ = 561084432.

The previous prime is 561166591. The next prime is 561166637. The reversal of 561166601 is 106661165.

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

It can be written as a sum of positive squares in 2 ways, for example, as 498360976 + 62805625 = 22324^2 + 7925^2 .

It is a cyclic number.

It is not a de Polignac number, because 561166601 - 2⁶ = 561166537 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (561162601) 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 in 3 ways as a sum of consecutive naturals, for example, 29810 + ... + 44843.

It is an arithmetic number, because the mean of its divisors is an integer number (140312193).

Almost surely, 2^561166601 is an apocalyptic number.

It is an amenable number.

561166601 is a deficient number, since it is larger than the sum of its proper divisors (82171).

561166601 is an equidigital number, since it uses as much as digits as its factorization.

561166601 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82170.

The product of its (nonzero) digits is 6480, while the sum is 32.

The square root of 561166601 is about 23688.9552534509. The cubic root of 561166601 is about 824.8290314834.

The spelling of 561166601 in words is "five hundred sixty-one million, one hundred sixty-six thousand, six hundred one".