221028480 has 128 divisors (see below), whose sum is σ = 782870400. Its totient is φ = 58936320.

The previous prime is 221028473. The next prime is 221028503. The reversal of 221028480 is 84820122.

It is a tau number, because it is divible by the number of its divisors (128).

It is a super-2 number, since 2×221028480² = 97707177942220800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

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, 10885 + ... + 23675.

It is an arithmetic number, because the mean of its divisors is an integer number (6116175).

Almost surely, 2^221028480 is an apocalyptic number.

221028480 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 221028480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (391435200).

221028480 is an abundant number, since it is smaller than the sum of its proper divisors (561841920).

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

221028480 is a wasteful number, since it uses less digits than its factorization.

221028480 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12819 (or 12801 counting only the distinct ones).

The product of its (nonzero) digits is 2048, while the sum is 27.

The square root of 221028480 is about 14867.0266025187. The cubic root of 221028480 is about 604.6203295979.

The spelling of 221028480 in words is "two hundred twenty-one million, twenty-eight thousand, four hundred eighty".