21211021211101 has 4 divisors (see below), whose sum is σ = 21421031322204. Its totient is φ = 21001011100000.

The previous prime is 21211021211069. The next prime is 21211021211131. The reversal of 21211021211101 is 10111212011212.

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

It can be written as a sum of positive squares in 2 ways, for example, as 17373065946201 + 3837955264900 = 4168101^2 + 1959070^2 .

It is a cyclic number.

It is not a de Polignac number, because 21211021211101 - 2⁵ = 21211021211069 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 (21211021211131) 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, 105005055400 + ... + 105005055601.

It is an arithmetic number, because the mean of its divisors is an integer number (5355257830551).

Almost surely, 2^{21211021211101} is an apocalyptic number.

It is an amenable number.

21211021211101 is a deficient number, since it is larger than the sum of its proper divisors (210010111103).

21211021211101 is a wasteful number, since it uses less digits than its factorization.

21211021211101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 210010111102.

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

Adding to 21211021211101 its reverse (10111212011212), we get a palindrome (31322233222313).

The spelling of 21211021211101 in words is "twenty-one trillion, two hundred eleven billion, twenty-one million, two hundred eleven thousand, one hundred one".