28439507 has 4 divisors (see below), whose sum is σ = 28497000. Its totient is φ = 28382016.

The previous prime is 28439503. The next prime is 28439531. The reversal of 28439507 is 70593482.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 28439507 - 2² = 28439503 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28439503) 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, 27998 + ... + 28995.

It is an arithmetic number, because the mean of its divisors is an integer number (7124250).

Almost surely, 2^28439507 is an apocalyptic number.

28439507 is a deficient number, since it is larger than the sum of its proper divisors (57493).

28439507 is an equidigital number, since it uses as much as digits as its factorization.

28439507 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57492.

The product of its (nonzero) digits is 60480, while the sum is 38.

The square root of 28439507 is about 5332.8704278278. The cubic root of 28439507 is about 305.2394679412.

The spelling of 28439507 in words is "twenty-eight million, four hundred thirty-nine thousand, five hundred seven".