321220243 has 8 divisors (see below), whose sum is σ = 324401840. Its totient is φ = 318051360.

The previous prime is 321220223. The next prime is 321220247. The reversal of 321220243 is 342022123.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-321220243 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 321220243.

It is not an unprimeable number, because it can be changed into a prime (321220247) 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, 52273 + ... + 58093.

It is an arithmetic number, because the mean of its divisors is an integer number (40550230).

Almost surely, 2^321220243 is an apocalyptic number.

321220243 is a deficient number, since it is larger than the sum of its proper divisors (3181597).

321220243 is a wasteful number, since it uses less digits than its factorization.

321220243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6357.

The product of its (nonzero) digits is 576, while the sum is 19.

The square root of 321220243 is about 17922.6181960114. The cubic root of 321220243 is about 684.8586868174.

Adding to 321220243 its reverse (342022123), we get a palindrome (663242366).

The spelling of 321220243 in words is "three hundred twenty-one million, two hundred twenty thousand, two hundred forty-three".