21021102111 has 8 divisors (see below), whose sum is σ = 28029755520. Its totient is φ = 14013258392.

The previous prime is 21021102107. The next prime is 21021102209. The reversal of 21021102111 is 11120112012.

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 21021102111 - 2² = 21021102107 is a prime.

It is a super-2 number, since 2×21021102111² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21021109111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 139005 + ... + 247718.

It is an arithmetic number, because the mean of its divisors is an integer number (3503719440).

Almost surely, 2^21021102111 is an apocalyptic number.

21021102111 is a deficient number, since it is larger than the sum of its proper divisors (7008653409).

21021102111 is a wasteful number, since it uses less digits than its factorization.

21021102111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 404845.

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

Adding to 21021102111 its reverse (11120112012), we get a palindrome (32141214123).

Subtracting from 21021102111 its reverse (11120112012), we obtain a palindrome (9900990099).

The spelling of 21021102111 in words is "twenty-one billion, twenty-one million, one hundred two thousand, one hundred eleven".