221342240 has 96 divisors (see below), whose sum is σ = 600929280. Its totient is φ = 75469824.

The previous prime is 221342203. The next prime is 221342299. The reversal of 221342240 is 42243122.

It is a Harshad number since it is a multiple of its sum of digits (20).

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 15 ways as a sum of consecutive naturals, for example, 256049 + ... + 256911.

It is an arithmetic number, because the mean of its divisors is an integer number (6259680).

Almost surely, 2^221342240 is an apocalyptic number.

221342240 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 221342240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (300464640).

221342240 is an abundant number, since it is smaller than the sum of its proper divisors (379587040).

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

221342240 is a wasteful number, since it uses less digits than its factorization.

221342240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1114 (or 1106 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 20.

The square root of 221342240 is about 14877.5750712272. The cubic root of 221342240 is about 604.9062896999.

Adding to 221342240 its reverse (42243122), we get a palindrome (263585362).

The spelling of 221342240 in words is "two hundred twenty-one million, three hundred forty-two thousand, two hundred forty".