21201211100 has 36 divisors (see below), whose sum is σ = 46019492064. Its totient is φ = 8478113280.

The previous prime is 21201211093. The next prime is 21201211111. The reversal of 21201211100 is 111210212.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 354572 + ... + 410028.

It is an arithmetic number, because the mean of its divisors is an integer number (1278319224).

Almost surely, 2^21201211100 is an apocalyptic number.

21201211100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21201211100 is an abundant number, since it is smaller than the sum of its proper divisors (24818280964).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21201211100 is a wasteful number, since it uses less digits than its factorization.

21201211100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59294 (or 59287 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 21201211100 its reverse (111210212), we get a palindrome (21312421312).

The spelling of 21201211100 in words is "twenty-one billion, two hundred one million, two hundred eleven thousand, one hundred".