865011 has 16 divisors (see below), whose sum is σ = 1396224. Its totient is φ = 465024.

The previous prime is 865003. The next prime is 865043. The reversal of 865011 is 110568.

It is not a de Polignac number, because 865011 - 2³ = 865003 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is not an unprimeable number, because it can be changed into a prime (865001) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 855 + ... + 1568.

It is an arithmetic number, because the mean of its divisors is an integer number (87264).

2⁸⁶⁵⁰¹¹ is an apocalyptic number.

865011 is a deficient number, since it is larger than the sum of its proper divisors (531213).

865011 is a wasteful number, since it uses less digits than its factorization.

865011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2450.

The product of its (nonzero) digits is 240, while the sum is 21.

The square root of 865011 is about 930.0596755047. The cubic root of 865011 is about 95.2811982315.

Adding to 865011 its reverse (110568), we get a palindrome (975579).

The spelling of 865011 in words is "eight hundred sixty-five thousand, eleven".