221221100120020 has 144 divisors (see below), whose sum is σ = 634889087739648. Its totient is φ = 63648028765440.

The previous prime is 221221100119933. The next prime is 221221100120063. The reversal of 221221100120020 is 20021001122122.

It is a happy number.

221221100120020 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 221221100119976 and 221221100120003.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 789145932 + ... + 789426211.

It is an arithmetic number, because the mean of its divisors is an integer number (4408951998192).

Almost surely, 2^{221221100120020} is an apocalyptic number.

221221100120020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221221100120020 is an abundant number, since it is smaller than the sum of its proper divisors (413667987619628).

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

221221100120020 is a wasteful number, since it uses less digits than its factorization.

221221100120020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1578572190 (or 1578572181 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 221221100120020 its reverse (20021001122122), we get a palindrome (241242101242142).

The spelling of 221221100120020 in words is "two hundred twenty-one trillion, two hundred twenty-one billion, one hundred million, one hundred twenty thousand, twenty".