21211221110101 has 16 divisors (see below), whose sum is σ = 24505961568768. Its totient is φ = 18169248438000.

The previous prime is 21211221110071. The next prime is 21211221110119. The reversal of 21211221110101 is 10101112211212.

It is not a de Polignac number, because 21211221110101 - 2¹³ = 21211221101909 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 (21211221110201) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 625645875 + ... + 625679776.

It is an arithmetic number, because the mean of its divisors is an integer number (1531622598048).

Almost surely, 2^{21211221110101} is an apocalyptic number.

It is an amenable number.

21211221110101 is a deficient number, since it is larger than the sum of its proper divisors (3294740458667).

21211221110101 is a wasteful number, since it uses less digits than its factorization.

21211221110101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1251325752.

The product of its (nonzero) digits is 16, while the sum is 16.

Adding to 21211221110101 its reverse (10101112211212), we get a palindrome (31312333321313).

The spelling of 21211221110101 in words is "twenty-one trillion, two hundred eleven billion, two hundred twenty-one million, one hundred ten thousand, one hundred one".