21222201100 has 18 divisors (see below), whose sum is σ = 46052176604. Its totient is φ = 8488880400.

The previous prime is 21222201047. The next prime is 21222201149. The reversal of 21222201100 is 110222212.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 106110906 + ... + 106111105.

Almost surely, 2^21222201100 is an apocalyptic number.

21222201100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21222201100 is an abundant number, since it is smaller than the sum of its proper divisors (24829975504).

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

21222201100 is a wasteful number, since it uses less digits than its factorization.

21222201100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 212222025 (or 212222018 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 21222201100 its reverse (110222212), we get a palindrome (21332423312).

The spelling of 21222201100 in words is "twenty-one billion, two hundred twenty-two million, two hundred one thousand, one hundred".