28512773858 has 4 divisors (see below), whose sum is σ = 42769160790. Its totient is φ = 14256386928.

The previous prime is 28512773843. The next prime is 28512773897. The reversal of 28512773858 is 85837721582.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 85837721582 = 2 ⋅42918860791.

It can be written as a sum of positive squares in only one way, i.e., 25073772409 + 3439001449 = 158347^2 + 58643^2 .

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7128193463 + ... + 7128193466.

Almost surely, 2^28512773858 is an apocalyptic number.

28512773858 is a deficient number, since it is larger than the sum of its proper divisors (14256386932).

28512773858 is a wasteful number, since it uses less digits than its factorization.

28512773858 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14256386931.

The product of its digits is 7526400, while the sum is 56.

The spelling of 28512773858 in words is "twenty-eight billion, five hundred twelve million, seven hundred seventy-three thousand, eight hundred fifty-eight".