28003239 has 40 divisors (see below), whose sum is σ = 46574352. Its totient is φ = 16623360.

The previous prime is 28003231. The next prime is 28003249. The reversal of 28003239 is 93230082.

It is not a de Polignac number, because 28003239 - 2³ = 28003231 is a prime.

It is a super-2 number, since 2×28003239² = 1568362788982242, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28003231) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 46927 + ... + 47519.

Almost surely, 2^28003239 is an apocalyptic number.

28003239 is a deficient number, since it is larger than the sum of its proper divisors (18571113).

28003239 is a wasteful number, since it uses less digits than its factorization.

28003239 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 669 (or 660 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 27.

The square root of 28003239 is about 5291.8086700107. The cubic root of 28003239 is about 303.6706056786.

It can be divided in two parts, 2 and 8003239, that added together give a square (8003241 = 2829²).

The spelling of 28003239 in words is "twenty-eight million, three thousand, two hundred thirty-nine".