13781128 has 16 divisors (see below), whose sum is σ = 25883280. Its totient is φ = 6878928.

The previous prime is 13781123. The next prime is 13781129. The reversal of 13781128 is 82118731.

It is a happy number.

It is a nialpdrome in base 8.

It is a self number, because there is not a number n which added to its sum of digits gives 13781128.

It is not an unprimeable number, because it can be changed into a prime (13781123) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5575 + ... + 7657.

It is an arithmetic number, because the mean of its divisors is an integer number (1617705).

Almost surely, 2^13781128 is an apocalyptic number.

It is an amenable number.

13781128 is a deficient number, since it is larger than the sum of its proper divisors (12102152).

13781128 is a wasteful number, since it uses less digits than its factorization.

13781128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2916 (or 2912 counting only the distinct ones).

The product of its digits is 2688, while the sum is 31.

The square root of 13781128 is about 3712.2941693783. The cubic root of 13781128 is about 239.7516412281.

Adding to 13781128 its reverse (82118731), we get a palindrome (95899859).

The spelling of 13781128 in words is "thirteen million, seven hundred eighty-one thousand, one hundred twenty-eight".