221101220002121 has 4 divisors (see below), whose sum is σ = 222457669204752. Its totient is φ = 219744770799492.

The previous prime is 221101220002097. The next prime is 221101220002151. The reversal of 221101220002121 is 121200022101122.

221101220002121 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 221101220002121 - 2²² = 221101215807817 is a prime.

It is a super-2 number, since 2×221101220002121² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 221101220002121.

It is not an unprimeable number, because it can be changed into a prime (221101220002151) 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, 678224601071 + ... + 678224601396.

It is an arithmetic number, because the mean of its divisors is an integer number (55614417301188).

Almost surely, 2^{221101220002121} is an apocalyptic number.

It is an amenable number.

221101220002121 is a deficient number, since it is larger than the sum of its proper divisors (1356449202631).

221101220002121 is a wasteful number, since it uses less digits than its factorization.

221101220002121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1356449202630.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 221101220002121 its reverse (121200022101122), we get a palindrome (342301242103243).

The spelling of 221101220002121 in words is "two hundred twenty-one trillion, one hundred one billion, two hundred twenty million, two thousand, one hundred twenty-one".