221449284 has 72 divisors (see below), whose sum is σ = 648805248. Its totient is φ = 62375040.

The previous prime is 221449273. The next prime is 221449297. The reversal of 221449284 is 482944122.

It is a super-2 number, since 2×221449284² = 98079570768225312, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 11704 + ... + 24080.

It is an arithmetic number, because the mean of its divisors is an integer number (9011184).

Almost surely, 2^221449284 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 221449284, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (324402624).

221449284 is an abundant number, since it is smaller than the sum of its proper divisors (427355964).

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

221449284 is a wasteful number, since it uses less digits than its factorization.

221449284 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12465 (or 12460 counting only the distinct ones).

The product of its digits is 36864, while the sum is 36.

The square root of 221449284 is about 14881.1721312536. The cubic root of 221449284 is about 605.0037875136.

The spelling of 221449284 in words is "two hundred twenty-one million, four hundred forty-nine thousand, two hundred eighty-four".