28003438 has 8 divisors (see below), whose sum is σ = 42162120. Its totient is φ = 13949400.

The previous prime is 28003433. The next prime is 28003439. The reversal of 28003438 is 83430082.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28003433) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25488 + ... + 26563.

It is an arithmetic number, because the mean of its divisors is an integer number (5270265).

Almost surely, 2^28003438 is an apocalyptic number.

28003438 is a deficient number, since it is larger than the sum of its proper divisors (14158682).

28003438 is a wasteful number, since it uses less digits than its factorization.

28003438 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52322.

The product of its (nonzero) digits is 4608, while the sum is 28.

The square root of 28003438 is about 5291.8274726223. The cubic root of 28003438 is about 303.6713250038.

It can be divided in two parts, 28003 and 438, that added together give a triangular number (28441 = T₂₃₈).

The spelling of 28003438 in words is "twenty-eight million, three thousand, four hundred thirty-eight".