21221211101 has 8 divisors (see below), whose sum is σ = 21454486200. Its totient is φ = 20988390400.

The previous prime is 21221211097. The next prime is 21221211113. The reversal of 21221211101 is 10111212212.

It can be written as a sum of positive squares in 4 ways, for example, as 406224025 + 20814987076 = 20155^2 + 144274^2 .

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 21221211101 - 2² = 21221211097 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 (21221216101) 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, 19256 + ... + 206913.

It is an arithmetic number, because the mean of its divisors is an integer number (2681810775).

Almost surely, 2^21221211101 is an apocalyptic number.

It is an amenable number.

21221211101 is a deficient number, since it is larger than the sum of its proper divisors (233275099).

21221211101 is a wasteful number, since it uses less digits than its factorization.

21221211101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 227199.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 21221211101 its reverse (10111212212), we get a palindrome (31332423313).

The spelling of 21221211101 in words is "twenty-one billion, two hundred twenty-one million, two hundred eleven thousand, one hundred one".