21221011101011 has 4 divisors (see below), whose sum is σ = 21309065089224. Its totient is φ = 21132957112800.

The previous prime is 21221011100987. The next prime is 21221011101023. The reversal of 21221011101011 is 11010111012212.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21221011101011 - 2³⁴ = 21203831231827 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21221011101811) 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, 44026993745 + ... + 44026994226.

It is an arithmetic number, because the mean of its divisors is an integer number (5327266272306).

Almost surely, 2^{21221011101011} is an apocalyptic number.

21221011101011 is a deficient number, since it is larger than the sum of its proper divisors (88053988213).

21221011101011 is an equidigital number, since it uses as much as digits as its factorization.

21221011101011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 88053988212.

The product of its (nonzero) digits is 8, while the sum is 14.

Adding to 21221011101011 its reverse (11010111012212), we get a palindrome (32231122113223).

The spelling of 21221011101011 in words is "twenty-one trillion, two hundred twenty-one billion, eleven million, one hundred one thousand, eleven".