221100202100 has 36 divisors (see below), whose sum is σ = 496331839500. Its totient is φ = 85390421760.

The previous prime is 221100202091. The next prime is 221100202201. The reversal of 221100202100 is 1202001122.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 1180472164 + 219919729936 = 34358^2 + 468956^2 .

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, 38117825 + ... + 38123624.

Almost surely, 2^221100202100 is an apocalyptic number.

221100202100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221100202100 is an abundant number, since it is smaller than the sum of its proper divisors (275231637400).

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

221100202100 is a wasteful number, since it uses less digits than its factorization.

221100202100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 76241492 (or 76241485 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 221100202100 its reverse (1202001122), we get a palindrome (222302203222).

The spelling of 221100202100 in words is "two hundred twenty-one billion, one hundred million, two hundred two thousand, one hundred".