12187728 has 120 divisors (see below), whose sum is σ = 39693888. Its totient is φ = 3419136.

The previous prime is 12187727. The next prime is 12187729. The reversal of 12187728 is 82778121.

It is a happy number.

12187728 is digitally balanced in base 2, base 4 and base 8, because in such bases it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (12187727) and next prime (12187729).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

12187728 is strictly pandigital in base 8.

It is a junction number, because it is equal to n+sod(n) for n = 12187692 and 12187701.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12187727) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 107800 + ... + 107912.

Almost surely, 2^12187728 is an apocalyptic number.

12187728 is a gapful number since it is divisible by the number (18) 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 12187728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (19846944).

12187728 is an abundant number, since it is smaller than the sum of its proper divisors (27506160).

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

12187728 is a wasteful number, since it uses less digits than its factorization.

12187728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 241 (or 232 counting only the distinct ones).

The product of its digits is 12544, while the sum is 36.

The square root of 12187728 is about 3491.0926656278. The cubic root of 12187728 is about 230.1305371154.

The spelling of 12187728 in words is "twelve million, one hundred eighty-seven thousand, seven hundred twenty-eight".