28717500 has 120 divisors (see below), whose sum is σ = 95869312. Its totient is φ = 6552000.

The previous prime is 28717499. The next prime is 28717553. The reversal of 28717500 is 571782.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 52227 + ... + 52773.

Almost surely, 2^28717500 is an apocalyptic number.

28717500 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28717500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (47934656).

28717500 is an abundant number, since it is smaller than the sum of its proper divisors (67151812).

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

28717500 is a wasteful number, since it uses less digits than its factorization.

28717500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 581 (or 564 counting only the distinct ones).

The product of its (nonzero) digits is 3920, while the sum is 30.

The square root of 28717500 is about 5358.8711497852. The cubic root of 28717500 is about 306.2308054053.

The spelling of 28717500 in words is "twenty-eight million, seven hundred seventeen thousand, five hundred".