221302321 has 4 divisors (see below), whose sum is σ = 222084592. Its totient is φ = 220520052.

The previous prime is 221302307. The next prime is 221302331. The reversal of 221302321 is 123203122.

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.

It is a cyclic number.

It is not a de Polignac number, because 221302321 - 2⁹ = 221301809 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 221302295 and 221302304.

It is not an unprimeable number, because it can be changed into a prime (221302331) 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, 390711 + ... + 391276.

It is an arithmetic number, because the mean of its divisors is an integer number (55521148).

Almost surely, 2^221302321 is an apocalyptic number.

It is an amenable number.

221302321 is a deficient number, since it is larger than the sum of its proper divisors (782271).

221302321 is an equidigital number, since it uses as much as digits as its factorization.

221302321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 782270.

The product of its (nonzero) digits is 144, while the sum is 16.

The square root of 221302321 is about 14876.2334278540. The cubic root of 221302321 is about 604.8699226302.

Adding to 221302321 its reverse (123203122), we get a palindrome (344505443).

The spelling of 221302321 in words is "two hundred twenty-one million, three hundred two thousand, three hundred twenty-one".