28402439 has 8 divisors (see below), whose sum is σ = 31044720. Its totient is φ = 25825536.

The previous prime is 28402433. The next prime is 28402453. The reversal of 28402439 is 93420482.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28402439 is a prime.

It is a super-2 number, since 2×28402439² = 1613397082297442, which contains 22 as substring.

It is a Duffinian number.

28402439 is a modest number, since divided by 2439 gives 284 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28402433) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15434 + ... + 17175.

It is an arithmetic number, because the mean of its divisors is an integer number (3880590).

Almost surely, 2^28402439 is an apocalyptic number.

28402439 is a deficient number, since it is larger than the sum of its proper divisors (2642281).

28402439 is a wasteful number, since it uses less digits than its factorization.

28402439 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32689.

The product of its (nonzero) digits is 13824, while the sum is 32.

The square root of 28402439 is about 5329.3938679741. The cubic root of 28402439 is about 305.1067940992.

The spelling of 28402439 in words is "twenty-eight million, four hundred two thousand, four hundred thirty-nine".