321683621993 has 4 divisors (see below), whose sum is σ = 338614338960. Its totient is φ = 304752905028.

The previous prime is 321683621989. The next prime is 321683622049. The reversal of 321683621993 is 399126386123.

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 321683621993 - 2² = 321683621989 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (321683621893) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8465358455 + ... + 8465358492.

It is an arithmetic number, because the mean of its divisors is an integer number (84653584740).

Almost surely, 2^321683621993 is an apocalyptic number.

It is an amenable number.

321683621993 is a deficient number, since it is larger than the sum of its proper divisors (16930716967).

321683621993 is a wasteful number, since it uses less digits than its factorization.

321683621993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16930716966.

The product of its digits is 2519424, while the sum is 53.

The spelling of 321683621993 in words is "three hundred twenty-one billion, six hundred eighty-three million, six hundred twenty-one thousand, nine hundred ninety-three".