221440421 has 8 divisors (see below), whose sum is σ = 235360320. Its totient is φ = 207747072.

The previous prime is 221440391. The next prime is 221440423. The reversal of 221440421 is 124044122.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 221440421 - 2¹⁰ = 221439397 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 221440393 and 221440402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221440423) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 54620 + ... + 58533.

It is an arithmetic number, because the mean of its divisors is an integer number (29420040).

Almost surely, 2^221440421 is an apocalyptic number.

It is an amenable number.

221440421 is a deficient number, since it is larger than the sum of its proper divisors (13919899).

221440421 is a wasteful number, since it uses less digits than its factorization.

221440421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 113275.

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

The square root of 221440421 is about 14880.8743358715. The cubic root of 221440421 is about 604.9957161093.

Adding to 221440421 its reverse (124044122), we get a palindrome (345484543).

The spelling of 221440421 in words is "two hundred twenty-one million, four hundred forty thousand, four hundred twenty-one".