21021002221100 has 72 divisors (see below), whose sum is σ = 52153481651040. Its totient is φ = 7204242769920.

The previous prime is 21021002221057. The next prime is 21021002221103. The reversal of 21021002221100 is 112220012012.

It is a super-2 number, since 2×21021002221100² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (14).

It is not an unprimeable number, because it can be changed into a prime (21021002221103) by changing a digit.

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, 4455365 + ... + 7867164.

It is an arithmetic number, because the mean of its divisors is an integer number (724353911820).

Almost surely, 2^{21021002221100} is an apocalyptic number.

21021002221100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21021002221100 is an abundant number, since it is smaller than the sum of its proper divisors (31132479429940).

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

21021002221100 is a wasteful number, since it uses less digits than its factorization.

21021002221100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12324987 (or 12324980 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 21021002221100 its reverse (112220012012), we get a palindrome (21133222233112).

The spelling of 21021002221100 in words is "twenty-one trillion, twenty-one billion, two million, two hundred twenty-one thousand, one hundred".