211221211101 has 4 divisors (see below), whose sum is σ = 281628281472. Its totient is φ = 140814140732.

The previous prime is 211221211081. The next prime is 211221211109. The reversal of 211221211101 is 101112122112.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 211221211101 - 2¹⁰ = 211221210077 is a prime.

It is a super-2 number, since 2×211221211101² (a number of 23 digits) contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211221211109) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 35203535181 + ... + 35203535186.

It is an arithmetic number, because the mean of its divisors is an integer number (70407070368).

Almost surely, 2^211221211101 is an apocalyptic number.

It is an amenable number.

211221211101 is a deficient number, since it is larger than the sum of its proper divisors (70407070371).

211221211101 is an equidigital number, since it uses as much as digits as its factorization.

211221211101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70407070370.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 211221211101 its reverse (101112122112), we get a palindrome (312333333213).

The spelling of 211221211101 in words is "two hundred eleven billion, two hundred twenty-one million, two hundred eleven thousand, one hundred one".