8564561 has 4 divisors (see below), whose sum is σ = 8576832. Its totient is φ = 8552292.

The previous prime is 8564557. The next prime is 8564593. The reversal of 8564561 is 1654658.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 8564561 - 2² = 8564557 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 (8564551) 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 3 ways as a sum of consecutive naturals, for example, 5021 + ... + 6506.

It is an arithmetic number, because the mean of its divisors is an integer number (2144208).

Almost surely, 2^8564561 is an apocalyptic number.

It is an amenable number.

8564561 is a deficient number, since it is larger than the sum of its proper divisors (12271).

8564561 is a wasteful number, since it uses less digits than its factorization.

8564561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12270.

The product of its digits is 28800, while the sum is 35.

The square root of 8564561 is about 2926.5271227173. The cubic root of 8564561 is about 204.5981499310.

Subtracting from 8564561 its reverse (1654658), we obtain a triangular number (6909903 = T₃₇₁₇).

It can be divided in two parts, 85 and 64561, that added together give a palindrome (64646).

The spelling of 8564561 in words is "eight million, five hundred sixty-four thousand, five hundred sixty-one".