8718561 has 6 divisors (see below), whose sum is σ = 12593490. Its totient is φ = 5812368.

The previous prime is 8718539. The next prime is 8718571. The reversal of 8718561 is 1658178.

8718561 is a `hidden beast` number, since 87 + 18 + 561 = 666.

It can be written as a sum of positive squares in only one way, i.e., 5089536 + 3629025 = 2256^2 + 1905^2 .

It is not a de Polignac number, because 8718561 - 2¹⁸ = 8456417 is a prime.

It is not an unprimeable number, because it can be changed into a prime (8718571) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 484356 + ... + 484373.

It is an arithmetic number, because the mean of its divisors is an integer number (2098915).

Almost surely, 2^8718561 is an apocalyptic number.

It is an amenable number.

8718561 is a deficient number, since it is larger than the sum of its proper divisors (3874929).

8718561 is a wasteful number, since it uses less digits than its factorization.

8718561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 968735 (or 968732 counting only the distinct ones).

The product of its digits is 13440, while the sum is 36.

The square root of 8718561 is about 2952.7209485490. The cubic root of 8718561 is about 205.8171705507.

The spelling of 8718561 in words is "eight million, seven hundred eighteen thousand, five hundred sixty-one".