221221011100 has 18 divisors (see below), whose sum is σ = 480049594304. Its totient is φ = 88488404400.

The previous prime is 221221011091. The next prime is 221221011131. The reversal of 221221011100 is 1110122122.

It is a congruent 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, 1106104956 + ... + 1106105155.

Almost surely, 2^221221011100 is an apocalyptic number.

221221011100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221221011100 is an abundant number, since it is smaller than the sum of its proper divisors (258828583204).

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

221221011100 is a wasteful number, since it uses less digits than its factorization.

221221011100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2212210125 (or 2212210118 counting only the distinct ones).

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

Adding to 221221011100 its reverse (1110122122), we get a palindrome (222331133222).

The spelling of 221221011100 in words is "two hundred twenty-one billion, two hundred twenty-one million, eleven thousand, one hundred".