28078447 has 8 divisors (see below), whose sum is σ = 29635200. Its totient is φ = 26529624.

The previous prime is 28078439. The next prime is 28078471. The reversal of 28078447 is 74487082.

It is a happy number.

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

It is not a de Polignac number, because 28078447 - 2³ = 28078439 is a prime.

It is a super-3 number, since 3×28078447³ (a number of 23 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28078487) 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, 6198 + ... + 9724.

It is an arithmetic number, because the mean of its divisors is an integer number (3704400).

Almost surely, 2^28078447 is an apocalyptic number.

28078447 is a deficient number, since it is larger than the sum of its proper divisors (1556753).

28078447 is a wasteful number, since it uses less digits than its factorization.

28078447 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3965.

The product of its (nonzero) digits is 100352, while the sum is 40.

The square root of 28078447 is about 5298.9099822511. The cubic root of 28078447 is about 303.9422176362.

The spelling of 28078447 in words is "twenty-eight million, seventy-eight thousand, four hundred forty-seven".