21301111211 has 4 divisors (see below), whose sum is σ = 21619038312. Its totient is φ = 20983184112.

The previous prime is 21301111199. The next prime is 21301111213. The reversal of 21301111211 is 11211110312.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21301111211 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21301111213) 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, 158963450 + ... + 158963583.

It is an arithmetic number, because the mean of its divisors is an integer number (5404759578).

Almost surely, 2^21301111211 is an apocalyptic number.

21301111211 is a deficient number, since it is larger than the sum of its proper divisors (317927101).

21301111211 is an equidigital number, since it uses as much as digits as its factorization.

21301111211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 317927100.

The product of its (nonzero) digits is 12, while the sum is 14.

Adding to 21301111211 its reverse (11211110312), we get a palindrome (32512221523).

The spelling of 21301111211 in words is "twenty-one billion, three hundred one million, one hundred eleven thousand, two hundred eleven".