13787728 has 10 divisors (see below), whose sum is σ = 26713754. Its totient is φ = 6893856.

The previous prime is 13787723. The next prime is 13787747. The reversal of 13787728 is 82778731.

It can be written as a sum of positive squares in only one way, i.e., 11916304 + 1871424 = 3452^2 + 1368^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13787723) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 430851 + ... + 430882.

Almost surely, 2^13787728 is an apocalyptic number.

It is an amenable number.

13787728 is a deficient number, since it is larger than the sum of its proper divisors (12926026).

13787728 is an equidigital number, since it uses as much as digits as its factorization.

13787728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 861741 (or 861735 counting only the distinct ones).

The product of its digits is 131712, while the sum is 43.

The square root of 13787728 is about 3713.1830011461. The cubic root of 13787728 is about 239.7899087365.

The spelling of 13787728 in words is "thirteen million, seven hundred eighty-seven thousand, seven hundred twenty-eight".