28109718 has 72 divisors (see below), whose sum is σ = 75535824. Its totient is φ = 7356960.

The previous prime is 28109651. The next prime is 28109747. The reversal of 28109718 is 81790182.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 214513 + ... + 214643.

Almost surely, 2^28109718 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28109718, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37767912).

28109718 is an abundant number, since it is smaller than the sum of its proper divisors (47426106).

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

28109718 is a wasteful number, since it uses less digits than its factorization.

28109718 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 290 (or 156 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 36.

The square root of 28109718 is about 5301.8598623502. The cubic root of 28109718 is about 304.0550093782.

It can be divided in two parts, 28 and 109718, that added together give a triangular number (109746 = T₄₆₈).

The spelling of 28109718 in words is "twenty-eight million, one hundred nine thousand, seven hundred eighteen".