28336639 has 6 divisors (see below), whose sum is σ = 28625136. Its totient is φ = 28051020.

The previous prime is 28336631. The next prime is 28336681. The reversal of 28336639 is 93663382.

It is not a de Polignac number, because 28336639 - 2³ = 28336631 is a prime.

It is a super-3 number, since 3×28336639³ (a number of 23 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28336631) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 9274 + ... + 11944.

It is an arithmetic number, because the mean of its divisors is an integer number (4770856).

Almost surely, 2^28336639 is an apocalyptic number.

28336639 is a deficient number, since it is larger than the sum of its proper divisors (288497).

28336639 is an equidigital number, since it uses as much as digits as its factorization.

28336639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2877 (or 2774 counting only the distinct ones).

The product of its digits is 139968, while the sum is 40.

The square root of 28336639 is about 5323.2169784821. The cubic root of 28336639 is about 304.8709980298.

The spelling of 28336639 in words is "twenty-eight million, three hundred thirty-six thousand, six hundred thirty-nine".