21211210220100 has 288 divisors, whose sum is σ = 62762257958400. Its totient is φ = 5529594470400.

The previous prime is 21211210220071. The next prime is 21211210220147. The reversal of 21211210220100 is 102201211212.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 21211210220100.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 6512497672 + ... + 6512500928.

It is an arithmetic number, because the mean of its divisors is an integer number (217924506800).

Almost surely, 2^{21211210220100} is an apocalyptic number.

21211210220100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21211210220100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31381128979200).

21211210220100 is an abundant number, since it is smaller than the sum of its proper divisors (41551047738300).

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

21211210220100 is a wasteful number, since it uses less digits than its factorization.

21211210220100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5983 (or 5976 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 21211210220100 its reverse (102201211212), we get a palindrome (21313411431312).

The spelling of 21211210220100 in words is "twenty-one trillion, two hundred eleven billion, two hundred ten million, two hundred twenty thousand, one hundred".