286861 has 4 divisors (see below), whose sum is σ = 294652. Its totient is φ = 279072.

The previous prime is 286859. The next prime is 286873. The reversal of 286861 is 168682.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 275625 + 11236 = 525^2 + 106^2 .

It is a cyclic number.

It is not a de Polignac number, because 286861 - 2¹ = 286859 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (286801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3840 + ... + 3913.

It is an arithmetic number, because the mean of its divisors is an integer number (73663).

2²⁸⁶⁸⁶¹ is an apocalyptic number.

It is an amenable number.

286861 is a deficient number, since it is larger than the sum of its proper divisors (7791).

286861 is an equidigital number, since it uses as much as digits as its factorization.

286861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7790.

The product of its digits is 4608, while the sum is 31.

The square root of 286861 is about 535.5940627005. The cubic root of 286861 is about 65.9513722002.

It can be divided in two parts, 28 and 6861, that added together give a square (6889 = 83²).

The spelling of 286861 in words is "two hundred eighty-six thousand, eight hundred sixty-one".