28686874 has 4 divisors (see below), whose sum is σ = 43030314. Its totient is φ = 14343436.

The previous prime is 28686869. The next prime is 28686881. The reversal of 28686874 is 47868682.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 47868682 = 2 ⋅23934341.

It can be written as a sum of positive squares in only one way, i.e., 20025625 + 8661249 = 4475^2 + 2943^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7171717 + ... + 7171720.

Almost surely, 2^28686874 is an apocalyptic number.

28686874 is a deficient number, since it is larger than the sum of its proper divisors (14343440).

28686874 is a wasteful number, since it uses less digits than its factorization.

28686874 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14343439.

The product of its digits is 1032192, while the sum is 49.

The square root of 28686874 is about 5356.0128827328. The cubic root of 28686874 is about 306.1219059469.

The spelling of 28686874 in words is "twenty-eight million, six hundred eighty-six thousand, eight hundred seventy-four".