321301691 has 2 divisors, whose sum is σ = 321301692. Its totient is φ = 321301690.

The previous prime is 321301661. The next prime is 321301693. The reversal of 321301691 is 196103123.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-321301691 is a prime.

Together with 321301693, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 321301691.

It is not a weakly prime, because it can be changed into another prime (321301693) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 160650845 + 160650846.

It is an arithmetic number, because the mean of its divisors is an integer number (160650846).

Almost surely, 2^321301691 is an apocalyptic number.

321301691 is a deficient number, since it is larger than the sum of its proper divisors (1).

321301691 is an equidigital number, since it uses as much as digits as its factorization.

321301691 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 972, while the sum is 26.

The square root of 321301691 is about 17924.8902646571. The cubic root of 321301691 is about 684.9165657522.

The spelling of 321301691 in words is "three hundred twenty-one million, three hundred one thousand, six hundred ninety-one".