28691256 has 64 divisors (see below), whose sum is σ = 78796800. Its totient is φ = 8633600.

The previous prime is 28691219. The next prime is 28691261. The reversal of 28691256 is 65219682.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 50140 + ... + 50708.

It is an arithmetic number, because the mean of its divisors is an integer number (1231200).

Almost surely, 2^28691256 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 28691256, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39398400).

28691256 is an abundant number, since it is smaller than the sum of its proper divisors (50105544).

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

28691256 is a wasteful number, since it uses less digits than its factorization.

28691256 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 780 (or 776 counting only the distinct ones).

The product of its digits is 51840, while the sum is 39.

The square root of 28691256 is about 5356.4219400641. The cubic root of 28691256 is about 306.1374921449.

The spelling of 28691256 in words is "twenty-eight million, six hundred ninety-one thousand, two hundred fifty-six".