221290272 has 144 divisors (see below), whose sum is σ = 750949920. Its totient is φ = 63213696.

The previous prime is 221290219. The next prime is 221290319. The reversal of 221290272 is 272092122.

It is a tau number, because it is divible by the number of its divisors (144).

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

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, 39723 + ... + 44949.

It is an arithmetic number, because the mean of its divisors is an integer number (5214930).

Almost surely, 2^221290272 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221290272, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (375474960).

221290272 is an abundant number, since it is smaller than the sum of its proper divisors (529659648).

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

221290272 is a wasteful number, since it uses less digits than its factorization.

221290272 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5260 (or 5239 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 27.

The square root of 221290272 is about 14875.8284475185. The cubic root of 221290272 is about 604.8589448722.

The spelling of 221290272 in words is "two hundred twenty-one million, two hundred ninety thousand, two hundred seventy-two".