211221212221 has 8 divisors (see below), whose sum is σ = 221105714688. Its totient is φ = 201528642000.

The previous prime is 211221212219. The next prime is 211221212239. The reversal of 211221212221 is 122212122112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 211221212221 - 2¹ = 211221212219 is a prime.

It is a super-2 number, since 2×211221212221² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211221212021) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 47980810 + ... + 47985211.

It is an arithmetic number, because the mean of its divisors is an integer number (27638214336).

Almost surely, 2^211221212221 is an apocalyptic number.

It is an amenable number.

211221212221 is a deficient number, since it is larger than the sum of its proper divisors (9884502467).

211221212221 is an equidigital number, since it uses as much as digits as its factorization.

211221212221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 95966123.

The product of its digits is 128, while the sum is 19.

Adding to 211221212221 its reverse (122212122112), we get a palindrome (333433334333).

The spelling of 211221212221 in words is "two hundred eleven billion, two hundred twenty-one million, two hundred twelve thousand, two hundred twenty-one".