13618728 has 24 divisors (see below), whose sum is σ = 36884250. Its totient is φ = 4539552.

The previous prime is 13618699. The next prime is 13618729. The reversal of 13618728 is 82781631.

13618728 is a `hidden beast` number, since 13 + 618 + 7 + 28 = 666.

It can be written as a sum of positive squares in only one way, i.e., 11985444 + 1633284 = 3462^2 + 1278^2 .

It is a tau number, because it is divible by the number of its divisors (24).

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

It is a junction number, because it is equal to n+sod(n) for n = 13618692 and 13618701.

It is not an unprimeable number, because it can be changed into a prime (13618729) 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 5 ways as a sum of consecutive naturals, for example, 94503 + ... + 94646.

Almost surely, 2^13618728 is an apocalyptic number.

13618728 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

13618728 is an abundant number, since it is smaller than the sum of its proper divisors (23265522).

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

13618728 is a wasteful number, since it uses less digits than its factorization.

13618728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 189161 (or 189154 counting only the distinct ones).

The product of its digits is 16128, while the sum is 36.

The square root of 13618728 is about 3690.3560803803. The cubic root of 13618728 is about 238.8061545681.

The spelling of 13618728 in words is "thirteen million, six hundred eighteen thousand, seven hundred twenty-eight".