21100011211 has 4 divisors (see below), whose sum is σ = 21114534352. Its totient is φ = 21085488072.

The previous prime is 21100011209. The next prime is 21100011217. The reversal of 21100011211 is 11211000112.

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 21100011211 - 2¹ = 21100011209 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21100011217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7259391 + ... + 7262296.

It is an arithmetic number, because the mean of its divisors is an integer number (5278633588).

Almost surely, 2^21100011211 is an apocalyptic number.

21100011211 is a deficient number, since it is larger than the sum of its proper divisors (14523141).

21100011211 is a wasteful number, since it uses less digits than its factorization.

21100011211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14523140.

The product of its (nonzero) digits is 4, while the sum is 10.

Adding to 21100011211 its reverse (11211000112), we get a palindrome (32311011323).

It can be divided in two parts, 211000112 and 11, that multiplied together give a palindrome (2321001232).

The spelling of 21100011211 in words is "twenty-one billion, one hundred million, eleven thousand, two hundred eleven".