86509 has 2 divisors, whose sum is σ = 86510. Its totient is φ = 86508.

The previous prime is 86501. The next prime is 86531. The reversal of 86509 is 90568.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 64009 + 22500 = 253^2 + 150^2 .

It is a cyclic number.

It is not a de Polignac number, because 86509 - 2³ = 86501 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (86501) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43254 + 43255.

It is an arithmetic number, because the mean of its divisors is an integer number (43255).

2⁸⁶⁵⁰⁹ is an apocalyptic number.

It is an amenable number.

86509 is a deficient number, since it is larger than the sum of its proper divisors (1).

86509 is an equidigital number, since it uses as much as digits as its factorization.

86509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2160, while the sum is 28.

The square root of 86509 is about 294.1241234581. The cubic root of 86509 is about 44.2269608858.

It can be divided in two parts, 86 and 509, that added together give a palindrome (595).

The spelling of 86509 in words is "eighty-six thousand, five hundred nine".