21221100111 has 8 divisors (see below), whose sum is σ = 28345600944. Its totient is φ = 14121999680.

The previous prime is 21221100101. The next prime is 21221100149. The reversal of 21221100111 is 11100112212.

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 21221100111 - 2¹³ = 21221091919 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21221100101) 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, 6348150 + ... + 6351491.

It is an arithmetic number, because the mean of its divisors is an integer number (3543200118).

Almost surely, 2^21221100111 is an apocalyptic number.

21221100111 is a deficient number, since it is larger than the sum of its proper divisors (7124500833).

21221100111 is a wasteful number, since it uses less digits than its factorization.

21221100111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12700201.

The product of its (nonzero) digits is 8, while the sum is 12.

Adding to 21221100111 its reverse (11100112212), we get a palindrome (32321212323).

The spelling of 21221100111 in words is "twenty-one billion, two hundred twenty-one million, one hundred thousand, one hundred eleven".