221144240 has 40 divisors (see below), whose sum is σ = 515608368. Its totient is φ = 88208640.

The previous prime is 221144237. The next prime is 221144243. The reversal of 221144240 is 42441122.

221144240 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (221144237) and next prime (221144243).

It is a tau number, because it is divible by the number of its divisors (40).

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

It is not an unprimeable number, because it can be changed into a prime (221144243) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 26135 + ... + 33545.

Almost surely, 2^221144240 is an apocalyptic number.

221144240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221144240 is an abundant number, since it is smaller than the sum of its proper divisors (294464128).

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

221144240 is a wasteful number, since it uses less digits than its factorization.

221144240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7797 (or 7791 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 20.

The square root of 221144240 is about 14870.9192721903. The cubic root of 221144240 is about 604.7258644654.

Adding to 221144240 its reverse (42441122), we get a palindrome (263585362).

The spelling of 221144240 in words is "two hundred twenty-one million, one hundred forty-four thousand, two hundred forty".