211221221100221 has 4 divisors (see below), whose sum is σ = 211662183984000. Its totient is φ = 210780258216444.

The previous prime is 211221221100199. The next prime is 211221221100233. The reversal of 211221221100221 is 122001122122112.

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 211221221100221 - 2¹⁴ = 211221221083837 is a prime.

It is a super-2 number, since 2×211221221100221² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 211221221100193 and 211221221100202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211221221108221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 220481441171 + ... + 220481442128.

It is an arithmetic number, because the mean of its divisors is an integer number (52915545996000).

Almost surely, 2^{211221221100221} is an apocalyptic number.

It is an amenable number.

211221221100221 is a deficient number, since it is larger than the sum of its proper divisors (440962883779).

211221221100221 is an equidigital number, since it uses as much as digits as its factorization.

211221221100221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 440962883778.

The product of its (nonzero) digits is 128, while the sum is 20.

Adding to 211221221100221 its reverse (122001122122112), we get a palindrome (333222343222333).

The spelling of 211221221100221 in words is "two hundred eleven trillion, two hundred twenty-one billion, two hundred twenty-one million, one hundred thousand, two hundred twenty-one".