221220230221 has 4 divisors (see below), whose sum is σ = 221452361532. Its totient is φ = 220988098912.

The previous prime is 221220230191. The next prime is 221220230299. The reversal of 221220230221 is 122032022122.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 32855550121 + 188364680100 = 181261^2 + 434010^2 .

It is a cyclic number.

It is not a de Polignac number, because 221220230221 - 2²⁷ = 221086012493 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221220230521) 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, 116064226 + ... + 116066131.

It is an arithmetic number, because the mean of its divisors is an integer number (55363090383).

Almost surely, 2^221220230221 is an apocalyptic number.

It is an amenable number.

221220230221 is a deficient number, since it is larger than the sum of its proper divisors (232131311).

221220230221 is an equidigital number, since it uses as much as digits as its factorization.

221220230221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 232131310.

The product of its (nonzero) digits is 384, while the sum is 19.

Adding to 221220230221 its reverse (122032022122), we get a palindrome (343252252343).

The spelling of 221220230221 in words is "two hundred twenty-one billion, two hundred twenty million, two hundred thirty thousand, two hundred twenty-one".