321663 has 8 divisors (see below), whose sum is σ = 432000. Its totient is φ = 212888.

The previous prime is 321661. The next prime is 321679. The reversal of 321663 is 366123.

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 321663 - 2¹ = 321661 is a prime.

321663 is a lucky number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 321663.

It is not an unprimeable number, because it can be changed into a prime (321661) 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, 238 + ... + 836.

It is an arithmetic number, because the mean of its divisors is an integer number (54000).

2³²¹⁶⁶³ is an apocalyptic number.

321663 is a deficient number, since it is larger than the sum of its proper divisors (110337).

321663 is a wasteful number, since it uses less digits than its factorization.

321663 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 781.

The product of its digits is 648, while the sum is 21.

The square root of 321663 is about 567.1534183975. The cubic root of 321663 is about 68.5173202867.

Adding to 321663 its reverse (366123), we get a palindrome (687786).

The spelling of 321663 in words is "three hundred twenty-one thousand, six hundred sixty-three".