126865 has 4 divisors (see below), whose sum is σ = 152244. Its totient is φ = 101488.

The previous prime is 126859. The next prime is 126913. The reversal of 126865 is 568621.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 568621 = 89 ⋅6389.

It can be written as a sum of positive squares in 2 ways, for example, as 16641 + 110224 = 129^2 + 332^2 .

It is a cyclic number.

It is not a de Polignac number, because 126865 - 2³ = 126857 is a prime.

It is a Duffinian number.

126865 is a lucky number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12682 + ... + 12691.

It is an arithmetic number, because the mean of its divisors is an integer number (38061).

2¹²⁶⁸⁶⁵ is an apocalyptic number.

It is an amenable number.

126865 is a deficient number, since it is larger than the sum of its proper divisors (25379).

126865 is an equidigital number, since it uses as much as digits as its factorization.

126865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25378.

The product of its digits is 2880, while the sum is 28.

The square root of 126865 is about 356.1811336946. The cubic root of 126865 is about 50.2474401145.

The spelling of 126865 in words is "one hundred twenty-six thousand, eight hundred sixty-five".