28724172056 has 16 divisors (see below), whose sum is σ = 54020540040. Its totient is φ = 14318694720.

The previous prime is 28724172053. The next prime is 28724172067. The reversal of 28724172056 is 65027142782.

It is a junction number, because it is equal to n+sod(n) for n = 28724171998 and 28724172016.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28724172053) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5421101 + ... + 5426396.

Almost surely, 2^28724172056 is an apocalyptic number.

It is an amenable number.

28724172056 is a deficient number, since it is larger than the sum of its proper divisors (25296367984).

28724172056 is a wasteful number, since it uses less digits than its factorization.

28724172056 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10847834 (or 10847830 counting only the distinct ones).

The product of its (nonzero) digits is 376320, while the sum is 44.

The spelling of 28724172056 in words is "twenty-eight billion, seven hundred twenty-four million, one hundred seventy-two thousand, fifty-six".