8188561 has 4 divisors (see below), whose sum is σ = 8388324. Its totient is φ = 7988800.

The previous prime is 8188559. The next prime is 8188567. The reversal of 8188561 is 1658818.

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 1134225 + 7054336 = 1065^2 + 2656^2 .

It is a cyclic number.

It is not a de Polignac number, because 8188561 - 2¹ = 8188559 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 8188561.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8188567) 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, 99820 + ... + 99901.

It is an arithmetic number, because the mean of its divisors is an integer number (2097081).

Almost surely, 2^8188561 is an apocalyptic number.

It is an amenable number.

8188561 is a deficient number, since it is larger than the sum of its proper divisors (199763).

8188561 is a wasteful number, since it uses less digits than its factorization.

8188561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 199762.

The product of its digits is 15360, while the sum is 37.

The square root of 8188561 is about 2861.5661795597. The cubic root of 8188561 is about 201.5591552557.

The spelling of 8188561 in words is "eight million, one hundred eighty-eight thousand, five hundred sixty-one".