28686847 has 4 divisors (see below), whose sum is σ = 32784976. Its totient is φ = 24588720.

The previous prime is 28686817. The next prime is 28686857. The reversal of 28686847 is 74868682.

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

It is a cyclic number.

It is not a de Polignac number, because 28686847 - 2¹⁹ = 28162559 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 28686847.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28686817) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2049054 + ... + 2049067.

It is an arithmetic number, because the mean of its divisors is an integer number (8196244).

Almost surely, 2^28686847 is an apocalyptic number.

28686847 is a deficient number, since it is larger than the sum of its proper divisors (4098129).

28686847 is an equidigital number, since it uses as much as digits as its factorization.

28686847 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4098128.

The product of its digits is 1032192, while the sum is 49.

The square root of 28686847 is about 5356.0103622006. The cubic root of 28686847 is about 306.1218099065.

The spelling of 28686847 in words is "twenty-eight million, six hundred eighty-six thousand, eight hundred forty-seven".