13117728 has 96 divisors (see below), whose sum is σ = 38779776. Its totient is φ = 3852288.

The previous prime is 13117723. The next prime is 13117739. The reversal of 13117728 is 82771131.

It is a tau number, because it is divible by the number of its divisors (96).

It is a hoax number, since the sum of its digits (30) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 13117695 and 13117704.

It is not an unprimeable number, because it can be changed into a prime (13117723) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 28476 + ... + 28932.

It is an arithmetic number, because the mean of its divisors is an integer number (403956).

Almost surely, 2^13117728 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 13117728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (19389888).

13117728 is an abundant number, since it is smaller than the sum of its proper divisors (25662048).

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

13117728 is a wasteful number, since it uses less digits than its factorization.

13117728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 506 (or 498 counting only the distinct ones).

The product of its digits is 2352, while the sum is 30.

The square root of 13117728 is about 3621.8404161420. The cubic root of 13117728 is about 235.8411264335.

Adding to 13117728 its reverse (82771131), we get a palindrome (95888859).

The spelling of 13117728 in words is "thirteen million, one hundred seventeen thousand, seven hundred twenty-eight".