21011222111 has 8 divisors (see below), whose sum is σ = 22975783248. Its totient is φ = 19055736000.

The previous prime is 21011222101. The next prime is 21011222149. The reversal of 21011222111 is 11122211012.

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 21011222111 - 2⁶ = 21011222047 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21011222101) 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, 2263910 + ... + 2273171.

It is an arithmetic number, because the mean of its divisors is an integer number (2871972906).

Almost surely, 2^21011222111 is an apocalyptic number.

21011222111 is a deficient number, since it is larger than the sum of its proper divisors (1964561137).

21011222111 is a wasteful number, since it uses less digits than its factorization.

21011222111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4537513.

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

Adding to 21011222111 its reverse (11122211012), we get a palindrome (32133433123).

The spelling of 21011222111 in words is "twenty-one billion, eleven million, two hundred twenty-two thousand, one hundred eleven".