321233521691 has 2 divisors, whose sum is σ = 321233521692. Its totient is φ = 321233521690.

The previous prime is 321233521649. The next prime is 321233521747. The reversal of 321233521691 is 196125332123.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-321233521691 is a prime.

It is not a weakly prime, because it can be changed into another prime (321233521601) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 160616760845 + 160616760846.

It is an arithmetic number, because the mean of its divisors is an integer number (160616760846).

Almost surely, 2^321233521691 is an apocalyptic number.

321233521691 is a deficient number, since it is larger than the sum of its proper divisors (1).

321233521691 is an equidigital number, since it uses as much as digits as its factorization.

321233521691 is an evil number, because the sum of its binary digits is even.

The product of its digits is 58320, while the sum is 38.

The spelling of 321233521691 in words is "three hundred twenty-one billion, two hundred thirty-three million, five hundred twenty-one thousand, six hundred ninety-one".