865971 has 10 divisors (see below), whose sum is σ = 1293732. Its totient is φ = 577260.

The previous prime is 865957. The next prime is 865979. The reversal of 865971 is 179568.

It is not a de Polignac number, because 865971 - 2¹⁰ = 864947 is a prime.

865971 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (865979) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 5265 + ... + 5426.

2⁸⁶⁵⁹⁷¹ is an apocalyptic number.

865971 is a gapful number since it is divisible by the number (81) formed by its first and last digit.

865971 is a deficient number, since it is larger than the sum of its proper divisors (427761).

865971 is a wasteful number, since it uses less digits than its factorization.

865971 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10703 (or 10694 counting only the distinct ones).

The product of its digits is 15120, while the sum is 36.

The square root of 865971 is about 930.5756283076. The cubic root of 865971 is about 95.3164332875.

The spelling of 865971 in words is "eight hundred sixty-five thousand, nine hundred seventy-one".