13321729 has 4 divisors (see below), whose sum is σ = 13540180. Its totient is φ = 13103280.

The previous prime is 13321699. The next prime is 13321741. The reversal of 13321729 is 92712331.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 92712331 = 233 ⋅397907.

It can be written as a sum of positive squares in 2 ways, for example, as 2772225 + 10549504 = 1665^2 + 3248^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-13321729 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 13321697 and 13321706.

It is not an unprimeable number, because it can be changed into a prime (13321129) 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, 109134 + ... + 109255.

It is an arithmetic number, because the mean of its divisors is an integer number (3385045).

Almost surely, 2^13321729 is an apocalyptic number.

It is an amenable number.

13321729 is a deficient number, since it is larger than the sum of its proper divisors (218451).

13321729 is an equidigital number, since it uses as much as digits as its factorization.

13321729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 218450.

The product of its digits is 2268, while the sum is 28.

The square root of 13321729 is about 3649.8943820335. The cubic root of 13321729 is about 237.0574080399.

The spelling of 13321729 in words is "thirteen million, three hundred twenty-one thousand, seven hundred twenty-nine".