221123440 has 40 divisors (see below), whose sum is σ = 514975968. Its totient is φ = 88300800.

The previous prime is 221123429. The next prime is 221123447. The reversal of 221123440 is 44321122.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221123447) 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, 54109 + ... + 58051.

Almost surely, 2^221123440 is an apocalyptic number.

221123440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221123440 is an abundant number, since it is smaller than the sum of its proper divisors (293852528).

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

221123440 is a wasteful number, since it uses less digits than its factorization.

221123440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4657 (or 4651 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 19.

The square root of 221123440 is about 14870.2199042247. The cubic root of 221123440 is about 604.7069044533.

Adding to 221123440 its reverse (44321122), we get a palindrome (265444562).

It can be divided in two parts, 22112 and 3440, that added together give a palindrome (25552).

The spelling of 221123440 in words is "two hundred twenty-one million, one hundred twenty-three thousand, four hundred forty".