321312421 has 4 divisors (see below), whose sum is σ = 321500844. Its totient is φ = 321124000.

The previous prime is 321312389. The next prime is 321312487. The reversal of 321312421 is 124213123.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 124213123 = 251 ⋅494873.

It can be written as a sum of positive squares in 2 ways, for example, as 82609921 + 238702500 = 9089^2 + 15450^2 .

It is a cyclic number.

It is not a de Polignac number, because 321312421 - 2⁵ = 321312389 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (321312491) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 91630 + ... + 95071.

It is an arithmetic number, because the mean of its divisors is an integer number (80375211).

Almost surely, 2^321312421 is an apocalyptic number.

It is an amenable number.

321312421 is a deficient number, since it is larger than the sum of its proper divisors (188423).

321312421 is a wasteful number, since it uses less digits than its factorization.

321312421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 188422.

The product of its digits is 288, while the sum is 19.

The square root of 321312421 is about 17925.1895666406. The cubic root of 321312421 is about 684.9241900226.

Adding to 321312421 its reverse (124213123), we get a palindrome (445525544).

The spelling of 321312421 in words is "three hundred twenty-one million, three hundred twelve thousand, four hundred twenty-one".