13987728 has 100 divisors (see below), whose sum is σ = 41591088. Its totient is φ = 4536000.

The previous prime is 13987723. The next prime is 13987733. The reversal of 13987728 is 82778931.

It is an interprime number because it is at equal distance from previous prime (13987723) and next prime (13987733).

It is not an unprimeable number, because it can be changed into a prime (13987723) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 55603 + ... + 55853.

Almost surely, 2^13987728 is an apocalyptic number.

13987728 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 13987728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20795544).

13987728 is an abundant number, since it is smaller than the sum of its proper divisors (27603360).

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

13987728 is a wasteful number, since it uses less digits than its factorization.

13987728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 314 (or 299 counting only the distinct ones).

The product of its digits is 169344, while the sum is 45.

The square root of 13987728 is about 3740.0171122603. The cubic root of 13987728 is about 240.9437837693.

The spelling of 13987728 in words is "thirteen million, nine hundred eighty-seven thousand, seven hundred twenty-eight".