221021200020100 has 144 divisors (see below), whose sum is σ = 517258602705600. Its totient is φ = 81698996736000.

The previous prime is 221021200020091. The next prime is 221021200020107. The reversal of 221021200020100 is 1020002120122.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (221021200020107) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 474255996 + ... + 474721804.

It is an arithmetic number, because the mean of its divisors is an integer number (3592073629900).

Almost surely, 2^{221021200020100} is an apocalyptic number.

221021200020100 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 221021200020100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (258629301352800).

221021200020100 is an abundant number, since it is smaller than the sum of its proper divisors (296237402685500).

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

221021200020100 is a wasteful number, since it uses less digits than its factorization.

221021200020100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 471974 (or 471967 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 221021200020100 its reverse (1020002120122), we get a palindrome (222041202140222).

The spelling of 221021200020100 in words is "two hundred twenty-one trillion, twenty-one billion, two hundred million, twenty thousand, one hundred".