221212212101221 has 8 divisors (see below), whose sum is σ = 241323440573088. Its totient is φ = 201101154858000.

The previous prime is 221212212101173. The next prime is 221212212101239. The reversal of 221212212101221 is 122101212212122.

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 221212212101221 - 2¹¹ = 221212212099173 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 221212212101192 and 221212212101201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221212212111221) 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, 40098435 + ... + 45280336.

It is an arithmetic number, because the mean of its divisors is an integer number (30165430071636).

Almost surely, 2^{221212212101221} is an apocalyptic number.

It is an amenable number.

221212212101221 is a deficient number, since it is larger than the sum of its proper divisors (20111228471867).

221212212101221 is a wasteful number, since it uses less digits than its factorization.

221212212101221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 85614323.

The product of its (nonzero) digits is 256, while the sum is 22.

Adding to 221212212101221 its reverse (122101212212122), we get a palindrome (343313424313343).

The spelling of 221212212101221 in words is "two hundred twenty-one trillion, two hundred twelve billion, two hundred twelve million, one hundred one thousand, two hundred twenty-one".