865787409 has 12 divisors (see below), whose sum is σ = 1262724736. Its totient is φ = 571587192.

The previous prime is 865787389. The next prime is 865787411. The reversal of 865787409 is 904787568.

It is not a de Polignac number, because 865787409 - 2⁷ = 865787281 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (865787479) 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, 466057 + ... + 467910.

Almost surely, 2^865787409 is an apocalyptic number.

It is an amenable number.

865787409 is a deficient number, since it is larger than the sum of its proper divisors (396937327).

865787409 is a wasteful number, since it uses less digits than its factorization.

865787409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 934076 (or 934073 counting only the distinct ones).

The product of its (nonzero) digits is 3386880, while the sum is 54.

The square root of 865787409 is about 29424.2656492902. The cubic root of 865787409 is about 953.0969692790.

The spelling of 865787409 in words is "eight hundred sixty-five million, seven hundred eighty-seven thousand, four hundred nine".