321613421 has 2 divisors, whose sum is σ = 321613422. Its totient is φ = 321613420.

The previous prime is 321613379. The next prime is 321613427. The reversal of 321613421 is 124316123.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 305725225 + 15888196 = 17485^2 + 3986^2 .

It is a cyclic number.

It is not a de Polignac number, because 321613421 - 2²⁶ = 254504557 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (321613427) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 160806710 + 160806711.

It is an arithmetic number, because the mean of its divisors is an integer number (160806711).

Almost surely, 2^321613421 is an apocalyptic number.

It is an amenable number.

321613421 is a deficient number, since it is larger than the sum of its proper divisors (1).

321613421 is an equidigital number, since it uses as much as digits as its factorization.

321613421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 864, while the sum is 23.

The square root of 321613421 is about 17933.5836072995. The cubic root of 321613421 is about 685.1379983752.

Adding to 321613421 its reverse (124316123), we get a palindrome (445929544).

The spelling of 321613421 in words is "three hundred twenty-one million, six hundred thirteen thousand, four hundred twenty-one".