221580216 has 96 divisors (see below), whose sum is σ = 705060720. Its totient is φ = 61977600.

The previous prime is 221580211. The next prime is 221580251. The reversal of 221580216 is 612085122.

It is a happy number.

221580216 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a self number, because there is not a number n which added to its sum of digits gives 221580216.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221580211) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 465 + ... + 21056.

Almost surely, 2^221580216 is an apocalyptic number.

221580216 is a gapful number since it is divisible by the number (26) 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 221580216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (352530360).

221580216 is an abundant number, since it is smaller than the sum of its proper divisors (483480504).

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

221580216 is a wasteful number, since it uses less digits than its factorization.

221580216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21557 (or 21550 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 27.

The square root of 221580216 is about 14885.5707314164. The cubic root of 221580216 is about 605.1230002858.

The spelling of 221580216 in words is "two hundred twenty-one million, five hundred eighty thousand, two hundred sixteen".