221455224 has 96 divisors (see below), whose sum is σ = 630283680. Its totient is φ = 70109952.

The previous prime is 221455207. The next prime is 221455231. The reversal of 221455224 is 422554122.

221455224 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 286102 + ... + 286874.

It is an arithmetic number, because the mean of its divisors is an integer number (6565455).

Almost surely, 2^221455224 is an apocalyptic number.

221455224 is a gapful number since it is divisible by the number (24) 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 221455224, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (315141840).

221455224 is an abundant number, since it is smaller than the sum of its proper divisors (408828456).

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

221455224 is a wasteful number, since it uses less digits than its factorization.

221455224 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 981 (or 974 counting only the distinct ones).

The product of its digits is 6400, while the sum is 27.

The square root of 221455224 is about 14881.3717109680. The cubic root of 221455224 is about 605.0091968640.

The spelling of 221455224 in words is "two hundred twenty-one million, four hundred fifty-five thousand, two hundred twenty-four".