21000220221008 has 120 divisors (see below), whose sum is σ = 49430959347072. Its totient is φ = 8464804227072.

The previous prime is 21000220221007. The next prime is 21000220221031. The reversal of 21000220221008 is 80012202200012.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21000220221007) 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, 46612310 + ... + 47060682.

Almost surely, 2^{21000220221008} is an apocalyptic number.

21000220221008 is a gapful number since it is divisible by the number (28) 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 21000220221008, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24715479673536).

21000220221008 is an abundant number, since it is smaller than the sum of its proper divisors (28430739126064).

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

21000220221008 is a wasteful number, since it uses less digits than its factorization.

21000220221008 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 449869 (or 449846 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 20.

The spelling of 21000220221008 in words is "twenty-one trillion, two hundred twenty million, two hundred twenty-one thousand, eight".