221403421 has 8 divisors (see below), whose sum is σ = 223257600. Its totient is φ = 219554448.

The previous prime is 221403401. The next prime is 221403439. The reversal of 221403421 is 124304122.

221403421 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 221403421 - 2¹⁹ = 220879133 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221403401) 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, 161280 + ... + 162646.

It is an arithmetic number, because the mean of its divisors is an integer number (27907200).

Almost surely, 2^221403421 is an apocalyptic number.

It is an amenable number.

221403421 is a deficient number, since it is larger than the sum of its proper divisors (1854179).

221403421 is a wasteful number, since it uses less digits than its factorization.

221403421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2603.

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

The square root of 221403421 is about 14879.6310774159. The cubic root of 221403421 is about 604.9620184247.

Adding to 221403421 its reverse (124304122), we get a palindrome (345707543).

The spelling of 221403421 in words is "two hundred twenty-one million, four hundred three thousand, four hundred twenty-one".