21000221120100 has 72 divisors (see below), whose sum is σ = 60761314374208. Its totient is φ = 5599996790400.

The previous prime is 21000221120089. The next prime is 21000221120141. The reversal of 21000221120100 is 102112200012.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 30857697 + ... + 31530903.

Almost surely, 2^{21000221120100} is an apocalyptic number.

21000221120100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21000221120100 is an abundant number, since it is smaller than the sum of its proper divisors (39761093254108).

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

21000221120100 is a wasteful number, since it uses less digits than its factorization.

21000221120100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 777205 (or 777198 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 21000221120100 its reverse (102112200012), we get a palindrome (21102333320112).

The spelling of 21000221120100 in words is "twenty-one trillion, two hundred twenty-one million, one hundred twenty thousand, one hundred".