865490985 has 12 divisors (see below), whose sum is σ = 1500184452. Its totient is φ = 461595168.

The previous prime is 865490963. The next prime is 865490987. The reversal of 865490985 is 589094568.

It is a happy number.

865490985 is a `hidden beast` number, since 8 + 6 + 549 + 0 + 98 + 5 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 136328976 + 729162009 = 11676^2 + 27003^2 .

It is not a de Polignac number, because 865490985 - 2¹¹ = 865488937 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (865490987) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 9616522 + ... + 9616611.

It is an arithmetic number, because the mean of its divisors is an integer number (125015371).

Almost surely, 2^865490985 is an apocalyptic number.

It is an amenable number.

865490985 is a deficient number, since it is larger than the sum of its proper divisors (634693467).

865490985 is a wasteful number, since it uses less digits than its factorization.

865490985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19233144 (or 19233141 counting only the distinct ones).

The product of its (nonzero) digits is 3110400, while the sum is 54.

The square root of 865490985 is about 29419.2281509900. The cubic root of 865490985 is about 952.9881846583.

The spelling of 865490985 in words is "eight hundred sixty-five million, four hundred ninety thousand, nine hundred eighty-five".