28781116 has 48 divisors (see below), whose sum is σ = 63695296. Its totient is φ = 11073024.

The previous prime is 28781101. The next prime is 28781141. The reversal of 28781116 is 61118782.

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, 12400 + ... + 14536.

Almost surely, 2^28781116 is an apocalyptic number.

28781116 is a gapful number since it is divisible by the number (26) 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 28781116, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31847648).

28781116 is an abundant number, since it is smaller than the sum of its proper divisors (34914180).

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

28781116 is a wasteful number, since it uses less digits than its factorization.

28781116 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2198 (or 2196 counting only the distinct ones).

The product of its digits is 5376, while the sum is 34.

The square root of 28781116 is about 5364.8034446753. The cubic root of 28781116 is about 306.4567629976.

Adding to 28781116 its reverse (61118782), we get a palindrome (89899898).

The spelling of 28781116 in words is "twenty-eight million, seven hundred eighty-one thousand, one hundred sixteen".