28878558 has 8 divisors (see below), whose sum is σ = 57757128. Its totient is φ = 9626184.

The previous prime is 28878533. The next prime is 28878571. The reversal of 28878558 is 85587882.

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

28878558 is an admirable number.

It is a super-2 number, since 2×28878558² = 1667942224318728, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 28878558.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2406541 + ... + 2406552.

It is an arithmetic number, because the mean of its divisors is an integer number (7219641).

Almost surely, 2^28878558 is an apocalyptic number.

28878558 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28878558 is a wasteful number, since it uses less digits than its factorization.

28878558 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4813098.

The product of its digits is 1433600, while the sum is 51.

The square root of 28878558 is about 5373.8773711353. The cubic root of 28878558 is about 306.8022224177.

The spelling of 28878558 in words is "twenty-eight million, eight hundred seventy-eight thousand, five hundred fifty-eight".