8661985 has 4 divisors (see below), whose sum is σ = 10394388. Its totient is φ = 6929584.

The previous prime is 8661977. The next prime is 8661997. The reversal of 8661985 is 5891668.

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 2331729 + 6330256 = 1527^2 + 2516^2 .

It is a cyclic number.

It is not a de Polignac number, because 8661985 - 2³ = 8661977 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 866194 + ... + 866203.

It is an arithmetic number, because the mean of its divisors is an integer number (2598597).

Almost surely, 2^8661985 is an apocalyptic number.

It is an amenable number.

8661985 is a deficient number, since it is larger than the sum of its proper divisors (1732403).

8661985 is a wasteful number, since it uses less digits than its factorization.

8661985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1732402.

The product of its digits is 103680, while the sum is 43.

The square root of 8661985 is about 2943.1250398174. The cubic root of 8661985 is about 205.3710116549.

The spelling of 8661985 in words is "eight million, six hundred sixty-one thousand, nine hundred eighty-five".