221408449 has 4 divisors (see below), whose sum is σ = 222401536. Its totient is φ = 220415364.

The previous prime is 221408441. The next prime is 221408543. The reversal of 221408449 is 944804122.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 944804122 = 2 ⋅472402061.

It is a cyclic number.

It is not a de Polignac number, because 221408449 - 2³ = 221408441 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221408441) 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 3 ways as a sum of consecutive naturals, for example, 496209 + ... + 496654.

It is an arithmetic number, because the mean of its divisors is an integer number (55600384).

Almost surely, 2^221408449 is an apocalyptic number.

It is an amenable number.

221408449 is a deficient number, since it is larger than the sum of its proper divisors (993087).

221408449 is an equidigital number, since it uses as much as digits as its factorization.

221408449 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 993086.

The product of its (nonzero) digits is 18432, while the sum is 34.

The square root of 221408449 is about 14879.8000322585. The cubic root of 221408449 is about 604.9665978872.

The spelling of 221408449 in words is "two hundred twenty-one million, four hundred eight thousand, four hundred forty-nine".