2231221 has 4 divisors (see below), whose sum is σ = 2234944. Its totient is φ = 2227500.

The previous prime is 2231219. The next prime is 2231269. The reversal of 2231221 is 1221322.

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: 1221322 = 2 ⋅610661.

It is a cyclic number.

It is not a de Polignac number, because 2231221 - 2¹ = 2231219 is a prime.

It is a super-3 number, since 3×2231221³ = 33323378124739820583, which contains 333 as substring.

It is a Duffinian number.

2231221 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2231821) 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, 735 + ... + 2236.

It is an arithmetic number, because the mean of its divisors is an integer number (558736).

2^2231221 is an apocalyptic number.

It is an amenable number.

2231221 is a deficient number, since it is larger than the sum of its proper divisors (3723).

2231221 is an equidigital number, since it uses as much as digits as its factorization.

2231221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3722.

The product of its digits is 48, while the sum is 13.

The square root of 2231221 is about 1493.7272173995. The cubic root of 2231221 is about 130.6714959285.

Adding to 2231221 its reverse (1221322), we get a palindrome (3452543).

It can be divided in two parts, 223 and 1221, that added together give a square (1444 = 38²).

The spelling of 2231221 in words is "two million, two hundred thirty-one thousand, two hundred twenty-one".