220421221 has 4 divisors (see below), whose sum is σ = 220486912. Its totient is φ = 220355532.

The previous prime is 220421197. The next prime is 220421281. The reversal of 220421221 is 122124022.

220421221 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 220421221 - 2⁵ = 220421189 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 220421195 and 220421204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (220421281) 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, 27525 + ... + 34618.

It is an arithmetic number, because the mean of its divisors is an integer number (55121728).

Almost surely, 2^220421221 is an apocalyptic number.

It is an amenable number.

220421221 is a deficient number, since it is larger than the sum of its proper divisors (65691).

220421221 is an equidigital number, since it uses as much as digits as its factorization.

220421221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65690.

The product of its (nonzero) digits is 128, while the sum is 16.

The square root of 220421221 is about 14846.5895410360. The cubic root of 220421221 is about 604.0661055449.

Adding to 220421221 its reverse (122124022), we get a palindrome (342545243).

The spelling of 220421221 in words is "two hundred twenty million, four hundred twenty-one thousand, two hundred twenty-one".