28786331 has 4 divisors (see below), whose sum is σ = 32898672. Its totient is φ = 24673992.

The previous prime is 28786319. The next prime is 28786343. The reversal of 28786331 is 13368782.

It is a happy number.

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

It is an interprime number because it is at equal distance from previous prime (28786319) and next prime (28786343).

It is not a de Polignac number, because 28786331 - 2¹⁴ = 28769947 is a prime.

It is a super-2 number, since 2×28786331² = 1657305704883122, which contains 22 as substring.

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 pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2056160 + ... + 2056173.

It is an arithmetic number, because the mean of its divisors is an integer number (8224668).

Almost surely, 2^28786331 is an apocalyptic number.

28786331 is a deficient number, since it is larger than the sum of its proper divisors (4112341).

28786331 is an equidigital number, since it uses as much as digits as its factorization.

28786331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4112340.

The product of its digits is 48384, while the sum is 38.

The square root of 28786331 is about 5365.2894609704. The cubic root of 28786331 is about 306.4752713777.

The spelling of 28786331 in words is "twenty-eight million, seven hundred eighty-six thousand, three hundred thirty-one".