13212221 has 4 divisors (see below), whose sum is σ = 14413344. Its totient is φ = 12011100.

The previous prime is 13212181. The next prime is 13212229. The reversal of 13212221 is 12221231.

It is a happy number.

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: 12221231 = 11 ⋅1111021.

It is a cyclic number.

It is not a de Polignac number, because 13212221 - 2¹⁴ = 13195837 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 13212196 and 13212205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13212229) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 600545 + ... + 600566.

It is an arithmetic number, because the mean of its divisors is an integer number (3603336).

Almost surely, 2^13212221 is an apocalyptic number.

13212221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

13212221 is a deficient number, since it is larger than the sum of its proper divisors (1201123).

13212221 is a wasteful number, since it uses less digits than its factorization.

13212221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1201122.

The product of its digits is 48, while the sum is 14.

The square root of 13212221 is about 3634.8618955883. The cubic root of 13212221 is about 236.4060626326.

Adding to 13212221 its reverse (12221231), we get a palindrome (25433452).

The spelling of 13212221 in words is "thirteen million, two hundred twelve thousand, two hundred twenty-one".