28786321 has 8 divisors (see below), whose sum is σ = 31463424. Its totient is φ = 26218560.

The previous prime is 28786319. The next prime is 28786343. The reversal of 28786321 is 12368782.

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

It is not a de Polignac number, because 28786321 - 2¹ = 28786319 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28786301) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 26785 + ... + 27838.

It is an arithmetic number, because the mean of its divisors is an integer number (3932928).

Almost surely, 2^28786321 is an apocalyptic number.

It is an amenable number.

28786321 is a deficient number, since it is larger than the sum of its proper divisors (2677103).

28786321 is a wasteful number, since it uses less digits than its factorization.

28786321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54671.

The product of its digits is 32256, while the sum is 37.

The square root of 28786321 is about 5365.2885290541. The cubic root of 28786321 is about 306.4752358891.

The spelling of 28786321 in words is "twenty-eight million, seven hundred eighty-six thousand, three hundred twenty-one".