221321012221 has 4 divisors (see below), whose sum is σ = 228460399744. Its totient is φ = 214181624700.

The previous prime is 221321012219. The next prime is 221321012239. The reversal of 221321012221 is 122210123122.

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 221321012221 - 2¹ = 221321012219 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 (221321010221) 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, 3569693715 + ... + 3569693776.

It is an arithmetic number, because the mean of its divisors is an integer number (57115099936).

Almost surely, 2^221321012221 is an apocalyptic number.

It is an amenable number.

221321012221 is a deficient number, since it is larger than the sum of its proper divisors (7139387523).

221321012221 is an equidigital number, since it uses as much as digits as its factorization.

221321012221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7139387522.

The product of its (nonzero) digits is 192, while the sum is 19.

Adding to 221321012221 its reverse (122210123122), we get a palindrome (343531135343).

The spelling of 221321012221 in words is "two hundred twenty-one billion, three hundred twenty-one million, twelve thousand, two hundred twenty-one".