21101123201221 has 8 divisors (see below), whose sum is σ = 24137043619904. Its totient is φ = 18070571344320.

The previous prime is 21101123201161. The next prime is 21101123201237. The reversal of 21101123201221 is 12210232110112.

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 21101123201221 - 2²⁷ = 21100988983493 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21101123201251) 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, 1342132020 + ... + 1342147741.

It is an arithmetic number, because the mean of its divisors is an integer number (3017130452488).

Almost surely, 2^{21101123201221} is an apocalyptic number.

It is an amenable number.

21101123201221 is a deficient number, since it is larger than the sum of its proper divisors (3035920418683).

21101123201221 is a wasteful number, since it uses less digits than its factorization.

21101123201221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2684280891.

The product of its (nonzero) digits is 96, while the sum is 19.

Adding to 21101123201221 its reverse (12210232110112), we get a palindrome (33311355311333).

The spelling of 21101123201221 in words is "twenty-one trillion, one hundred one billion, one hundred twenty-three million, two hundred one thousand, two hundred twenty-one".