28140939 has 20 divisors (see below), whose sum is σ = 42458416. Its totient is φ = 18572976.

The previous prime is 28140929. The next prime is 28140943. The reversal of 28140939 is 93904182.

It is not a de Polignac number, because 28140939 - 2⁵ = 28140907 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28140929) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 6657 + ... + 10029.

Almost surely, 2^28140939 is an apocalyptic number.

28140939 is a deficient number, since it is larger than the sum of its proper divisors (14317477).

28140939 is a wasteful number, since it uses less digits than its factorization.

28140939 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3488 (or 3479 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 36.

The square root of 28140939 is about 5304.8033893821. The cubic root of 28140939 is about 304.1675373549.

The spelling of 28140939 in words is "twenty-eight million, one hundred forty thousand, nine hundred thirty-nine".