21201022111 has 8 divisors (see below), whose sum is σ = 22466646000. Its totient is φ = 19950376320.

The previous prime is 21201022081. The next prime is 21201022123. The reversal of 21201022111 is 11122010212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21201022111 is a prime.

It is a super-2 number, since 2×21201022111² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21201022091 and 21201022100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21201022511) 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, 3741610 + ... + 3747271.

It is an arithmetic number, because the mean of its divisors is an integer number (2808330750).

Almost surely, 2^21201022111 is an apocalyptic number.

21201022111 is a deficient number, since it is larger than the sum of its proper divisors (1265623889).

21201022111 is a wasteful number, since it uses less digits than its factorization.

21201022111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7489049.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 21201022111 its reverse (11122010212), we get a palindrome (32323032323).

The spelling of 21201022111 in words is "twenty-one billion, two hundred one million, twenty-two thousand, one hundred eleven".