13309028 has 36 divisors (see below), whose sum is σ = 25659060. Its totient is φ = 6031872.

The previous prime is 13309007. The next prime is 13309031. The reversal of 13309028 is 82090331.

It can be written as a sum of positive squares in 6 ways, for example, as 1965604 + 11343424 = 1402^2 + 3368^2 .

It is a junction number, because it is equal to n+sod(n) for n = 13308988 and 13309006.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 33326 + ... + 33722.

Almost surely, 2^13309028 is an apocalyptic number.

It is an amenable number.

13309028 is a deficient number, since it is larger than the sum of its proper divisors (12350032).

13309028 is a wasteful number, since it uses less digits than its factorization.

13309028 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 464 (or 445 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 26.

The square root of 13309028 is about 3648.1540537647. The cubic root of 13309028 is about 236.9820468636.

Adding to 13309028 its reverse (82090331), we get a palindrome (95399359).

The spelling of 13309028 in words is "thirteen million, three hundred nine thousand, twenty-eight".