221000212100221 has 4 divisors (see below), whose sum is σ = 221000891709312. Its totient is φ = 220999532491132.

The previous prime is 221000212100201. The next prime is 221000212100237. The reversal of 221000212100221 is 122001212000122.

It is a happy number.

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 221000212100221 - 2⁵ = 221000212100189 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 221000212100195 and 221000212100204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221000212100201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 339316531 + ... + 339967216.

It is an arithmetic number, because the mean of its divisors is an integer number (55250222927328).

Almost surely, 2^{221000212100221} is an apocalyptic number.

It is an amenable number.

221000212100221 is a deficient number, since it is larger than the sum of its proper divisors (679609091).

221000212100221 is an equidigital number, since it uses as much as digits as its factorization.

221000212100221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 679609090.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 221000212100221 its reverse (122001212000122), we get a palindrome (343001424100343).

It can be divided in two parts, 22100021 and 2100221, that added together give a palindrome (24200242).

The spelling of 221000212100221 in words is "two hundred twenty-one trillion, two hundred twelve million, one hundred thousand, two hundred twenty-one".