221301221 has 4 divisors (see below), whose sum is σ = 222766944. Its totient is φ = 219835500.

The previous prime is 221301209. The next prime is 221301251. The reversal of 221301221 is 122103122.

It is a happy number.

221301221 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 a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 221301221 - 2²² = 217106917 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 221301196 and 221301205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221301251) 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, 732635 + ... + 732936.

It is an arithmetic number, because the mean of its divisors is an integer number (55691736).

Almost surely, 2^221301221 is an apocalyptic number.

It is an amenable number.

221301221 is a deficient number, since it is larger than the sum of its proper divisors (1465723).

221301221 is a wasteful number, since it uses less digits than its factorization.

221301221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1465722.

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

The square root of 221301221 is about 14876.1964560838. The cubic root of 221301221 is about 604.8689204446.

Adding to 221301221 its reverse (122103122), we get a palindrome (343404343).

The spelling of 221301221 in words is "two hundred twenty-one million, three hundred one thousand, two hundred twenty-one".