221417987780 has 96 divisors (see below), whose sum is σ = 523660878720. Its totient is φ = 77933076480.

The previous prime is 221417987779. The next prime is 221417987803. The reversal of 221417987780 is 87789714122.

221417987780 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1500551 + ... + 1641489.

It is an arithmetic number, because the mean of its divisors is an integer number (5454800820).

Almost surely, 2^221417987780 is an apocalyptic number.

221417987780 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 221417987780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (261830439360).

221417987780 is an abundant number, since it is smaller than the sum of its proper divisors (302242890940).

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

221417987780 is a wasteful number, since it uses less digits than its factorization.

221417987780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 141189 (or 141187 counting only the distinct ones).

The product of its (nonzero) digits is 3161088, while the sum is 56.

The spelling of 221417987780 in words is "two hundred twenty-one billion, four hundred seventeen million, nine hundred eighty-seven thousand, seven hundred eighty".