28786 has 8 divisors (see below), whose sum is σ = 44460. Its totient is φ = 13968.

The previous prime is 28771. The next prime is 28789. The reversal of 28786 is 68782.

28786 is nontrivially palindromic in base 9.

28786 is an esthetic number in base 9, because in such base its adjacent digits differ by 1.

It can be written as a sum of positive squares in 2 ways, for example, as 28561 + 225 = 169^2 + 15^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

28786 is an undulating number in base 9.

It is a plaindrome in base 12.

It is not an unprimeable number, because it can be changed into a prime (28789) by changing a digit.

28786 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

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, 121 + ... + 268.

2²⁸⁷⁸⁶ is an apocalyptic number.

28786 is a deficient number, since it is larger than the sum of its proper divisors (15674).

28786 is a wasteful number, since it uses less digits than its factorization.

28786 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 428.

The product of its digits is 5376, while the sum is 31.

The square root of 28786 is about 169.6643745752. The cubic root of 28786 is about 30.6474096703.

It can be divided in two parts, 287 and 86, that added together give a palindrome (373).

The spelling of 28786 in words is "twenty-eight thousand, seven hundred eighty-six".