13213021 has 4 divisors (see below), whose sum is σ = 13240000. Its totient is φ = 13186044.

The previous prime is 13213001. The next prime is 13213043. The reversal of 13213021 is 12031231.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 12031231 = 23 ⋅523097.

It is a cyclic number.

It is not a de Polignac number, because 13213021 - 2¹⁹ = 12688733 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 13212992 and 13213010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13213001) 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, 12741 + ... + 13738.

It is an arithmetic number, because the mean of its divisors is an integer number (3310000).

Almost surely, 2^13213021 is an apocalyptic number.

It is an amenable number.

13213021 is a deficient number, since it is larger than the sum of its proper divisors (26979).

13213021 is an equidigital number, since it uses as much as digits as its factorization.

13213021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26978.

The product of its (nonzero) digits is 36, while the sum is 13.

The square root of 13213021 is about 3634.9719393690. The cubic root of 13213021 is about 236.4108339987.

Adding to 13213021 its reverse (12031231), we get a palindrome (25244252).

The spelling of 13213021 in words is "thirteen million, two hundred thirteen thousand, twenty-one".