221201440 has 48 divisors (see below), whose sum is σ = 524180160. Its totient is φ = 88211200.

The previous prime is 221201369. The next prime is 221201447. The reversal of 221201440 is 44102122.

It is a Harshad number since it is a multiple of its sum of digits (16).

It is not an unprimeable number, because it can be changed into a prime (221201447) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 55515 + ... + 59365.

It is an arithmetic number, because the mean of its divisors is an integer number (10920420).

Almost surely, 2^221201440 is an apocalyptic number.

221201440 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 221201440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (262090080).

221201440 is an abundant number, since it is smaller than the sum of its proper divisors (302978720).

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

221201440 is a wasteful number, since it uses less digits than its factorization.

221201440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4225 (or 4217 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 16.

The square root of 221201440 is about 14872.8423645247. The cubic root of 221201440 is about 604.7779983691. Note that the first 3 decimals are identical.

Adding to 221201440 its reverse (44102122), we get a palindrome (265303562).

The spelling of 221201440 in words is "two hundred twenty-one million, two hundred one thousand, four hundred forty".