28172786 has 8 divisors (see below), whose sum is σ = 43056684. Its totient is φ = 13820560.

The previous prime is 28172759. The next prime is 28172803. The reversal of 28172786 is 68727182.

It can be written as a sum of positive squares in 2 ways, for example, as 26265625 + 1907161 = 5125^2 + 1381^2 .

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

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, 132785 + ... + 132996.

Almost surely, 2^28172786 is an apocalyptic number.

28172786 is a deficient number, since it is larger than the sum of its proper divisors (14883898).

28172786 is a wasteful number, since it uses less digits than its factorization.

28172786 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 265836.

The product of its digits is 75264, while the sum is 41.

The square root of 28172786 is about 5307.8042541149. The cubic root of 28172786 is about 304.2822358692.

The spelling of 28172786 in words is "twenty-eight million, one hundred seventy-two thousand, seven hundred eighty-six".