28709856 has 192 divisors, whose sum is σ = 98703360. Its totient is φ = 7948800.

The previous prime is 28709851. The next prime is 28709861. The reversal of 28709856 is 65890782.

It is an interprime number because it is at equal distance from previous prime (28709851) and next prime (28709861).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28709851) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 284206 + ... + 284306.

It is an arithmetic number, because the mean of its divisors is an integer number (514080).

Almost surely, 2^28709856 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 28709856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (49351680).

28709856 is an abundant number, since it is smaller than the sum of its proper divisors (69993504).

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

28709856 is a wasteful number, since it uses less digits than its factorization.

28709856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 174 (or 160 counting only the distinct ones).

The product of its (nonzero) digits is 241920, while the sum is 45.

The square root of 28709856 is about 5358.1578924104. The cubic root of 28709856 is about 306.2036322415.

The spelling of 28709856 in words is "twenty-eight million, seven hundred nine thousand, eight hundred fifty-six".