13340821 has 4 divisors (see below), whose sum is σ = 14367052. Its totient is φ = 12314592.

The previous prime is 13340813. The next prime is 13340849. The reversal of 13340821 is 12804331.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 8439025 + 4901796 = 2905^2 + 2214^2 .

It is a cyclic number.

It is not a de Polignac number, because 13340821 - 2³ = 13340813 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 13340792 and 13340801.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13340861) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 513096 + ... + 513121.

It is an arithmetic number, because the mean of its divisors is an integer number (3591763).

Almost surely, 2^13340821 is an apocalyptic number.

It is an amenable number.

13340821 is a deficient number, since it is larger than the sum of its proper divisors (1026231).

13340821 is a wasteful number, since it uses less digits than its factorization.

13340821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1026230.

The product of its (nonzero) digits is 576, while the sum is 22.

The square root of 13340821 is about 3652.5088637812. The cubic root of 13340821 is about 237.1706000452.

It can be divided in two parts, 13340 and 821, that added together give a square (14161 = 119²).

The spelling of 13340821 in words is "thirteen million, three hundred forty thousand, eight hundred twenty-one".