321423391 has 2 divisors, whose sum is σ = 321423392. Its totient is φ = 321423390.

The previous prime is 321423383. The next prime is 321423433. The reversal of 321423391 is 193324123.

It is a weak prime.

It is an emirp because it is prime and its reverse (193324123) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 321423391 - 2³ = 321423383 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (321423331) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 160711695 + 160711696.

It is an arithmetic number, because the mean of its divisors is an integer number (160711696).

Almost surely, 2^321423391 is an apocalyptic number.

321423391 is a deficient number, since it is larger than the sum of its proper divisors (1).

321423391 is an equidigital number, since it uses as much as digits as its factorization.

321423391 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3888, while the sum is 28.

The square root of 321423391 is about 17928.2846641836. The cubic root of 321423391 is about 685.0030305157.

The spelling of 321423391 in words is "three hundred twenty-one million, four hundred twenty-three thousand, three hundred ninety-one".