221021121221120 has 160 divisors (see below), whose sum is σ = 579633750083520. Its totient is φ = 80159251415040.

The previous prime is 221021121221113. The next prime is 221021121221143. The reversal of 221021121221120 is 21122121120122.

It is a tau number, because it is divible by the number of its divisors (160).

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 221021121221092 and 221021121221101.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 318074 + ... + 21027206.

It is an arithmetic number, because the mean of its divisors is an integer number (3622710938022).

Almost surely, 2^{221021121221120} is an apocalyptic number.

221021121221120 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 221021121221120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (289816875041760).

221021121221120 is an abundant number, since it is smaller than the sum of its proper divisors (358612628862400).

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

221021121221120 is a wasteful number, since it uses less digits than its factorization.

221021121221120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20709546 (or 20709530 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 20.

Adding to 221021121221120 its reverse (21122121120122), we get a palindrome (242143242341242).

The spelling of 221021121221120 in words is "two hundred twenty-one trillion, twenty-one billion, one hundred twenty-one million, two hundred twenty-one thousand, one hundred twenty".