221021221002120 has 768 divisors, whose sum is σ = 964649562439680. Its totient is φ = 42512593305600.

The previous prime is 221021221002119. The next prime is 221021221002149. The reversal of 221021221002120 is 21200122120122.

It is a happy number.

221021221002120 is a `hidden beast` number, since 2 + 210 + 21 + 221 + 0 + 0 + 212 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 221021221002093 and 221021221002102.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 14172952 + ... + 25355768.

It is an arithmetic number, because the mean of its divisors is an integer number (1256054117760).

Almost surely, 2^{221021221002120} is an apocalyptic number.

221021221002120 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 221021221002120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (482324781219840).

221021221002120 is an abundant number, since it is smaller than the sum of its proper divisors (743628341437560).

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

221021221002120 is a wasteful number, since it uses less digits than its factorization.

221021221002120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11182906 (or 11182899 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 221021221002120 its reverse (21200122120122), we get a palindrome (242221343122242).

The spelling of 221021221002120 in words is "two hundred twenty-one trillion, twenty-one billion, two hundred twenty-one million, two thousand, one hundred twenty".