28439405 has 8 divisors (see below), whose sum is σ = 34608384. Its totient is φ = 22430800.

The previous prime is 28439399. The next prime is 28439417. The reversal of 28439405 is 50493482.

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

It is a de Polignac number, because none of the positive numbers 2^k-28439405 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 39701 + ... + 40410.

It is an arithmetic number, because the mean of its divisors is an integer number (4326048).

Almost surely, 2^28439405 is an apocalyptic number.

It is an amenable number.

28439405 is a deficient number, since it is larger than the sum of its proper divisors (6168979).

28439405 is an equidigital number, since it uses as much as digits as its factorization.

28439405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80187.

The product of its (nonzero) digits is 34560, while the sum is 35.

The square root of 28439405 is about 5332.8608644892. The cubic root of 28439405 is about 305.2391030209.

The spelling of 28439405 in words is "twenty-eight million, four hundred thirty-nine thousand, four hundred five".