221430240 has 96 divisors (see below), whose sum is σ = 775020960. Its totient is φ = 59046912.

The previous prime is 221430239. The next prime is 221430247. The reversal of 221430240 is 42034122.

221430240 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (96).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221430247) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 21309 + ... + 29948.

It is an arithmetic number, because the mean of its divisors is an integer number (8073135).

Almost surely, 2^221430240 is an apocalyptic number.

221430240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221430240 is an abundant number, since it is smaller than the sum of its proper divisors (553590720).

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

221430240 is a wasteful number, since it uses less digits than its factorization.

221430240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51281 (or 51267 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 18.

The square root of 221430240 is about 14880.5322485454. The cubic root of 221430240 is about 604.9864441559.

Adding to 221430240 its reverse (42034122), we get a palindrome (263464362).

The spelling of 221430240 in words is "two hundred twenty-one million, four hundred thirty thousand, two hundred forty".