13021231 has 4 divisors (see below), whose sum is σ = 13338864. Its totient is φ = 12703600.

The previous prime is 13021219. The next prime is 13021247. The reversal of 13021231 is 13212031.

13021231 is nontrivially palindromic in base 15.

13021231 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13212031 = 7 ⋅1887433.

It is a cyclic number.

It is not a de Polignac number, because 13021231 - 2¹¹ = 13019183 is a prime.

It is a super-2 number, since 2×13021231² = 339104913510722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13021331) 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, 158755 + ... + 158836.

It is an arithmetic number, because the mean of its divisors is an integer number (3334716).

Almost surely, 2^13021231 is an apocalyptic number.

13021231 is a deficient number, since it is larger than the sum of its proper divisors (317633).

13021231 is an equidigital number, since it uses as much as digits as its factorization.

13021231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 317632.

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

The square root of 13021231 is about 3608.4942843241. The cubic root of 13021231 is about 235.2614021953.

Adding to 13021231 its reverse (13212031), we get a palindrome (26233262).

The spelling of 13021231 in words is "thirteen million, twenty-one thousand, two hundred thirty-one".