21001122211211 has 8 divisors (see below), whose sum is σ = 21124264181664. Its totient is φ = 20878000335360.

The previous prime is 21001122211189. The next prime is 21001122211247. The reversal of 21001122211211 is 11211222110012.

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 21001122211211 - 2¹⁴ = 21001122194827 is a prime.

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 21001122211211.

It is not an unprimeable number, because it can be changed into a prime (21001122217211) 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, 2924735 + ... + 7110296.

It is an arithmetic number, because the mean of its divisors is an integer number (2640533022708).

Almost surely, 2^{21001122211211} is an apocalyptic number.

21001122211211 is a deficient number, since it is larger than the sum of its proper divisors (123141970453).

21001122211211 is a wasteful number, since it uses less digits than its factorization.

21001122211211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10047301.

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 21001122211211 its reverse (11211222110012), we get a palindrome (32212344321223).

The spelling of 21001122211211 in words is "twenty-one trillion, one billion, one hundred twenty-two million, two hundred eleven thousand, two hundred eleven".