28787256 has 96 divisors (see below), whose sum is σ = 85503600. Its totient is φ = 8709120.

The previous prime is 28787249. The next prime is 28787257. The reversal of 28787256 is 65278782.

It is a super-2 number, since 2×28787256² = 1657412216019072, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28787257) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 35091 + ... + 35901.

Almost surely, 2^28787256 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28787256, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42751800).

28787256 is an abundant number, since it is smaller than the sum of its proper divisors (56716344).

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

28787256 is a wasteful number, since it uses less digits than its factorization.

28787256 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 869 (or 862 counting only the distinct ones).

The product of its digits is 376320, while the sum is 45.

The square root of 28787256 is about 5365.3756625235. The cubic root of 28787256 is about 306.4785540305.

The spelling of 28787256 in words is "twenty-eight million, seven hundred eighty-seven thousand, two hundred fifty-six".