321618421 has 4 divisors (see below), whose sum is σ = 321711052. Its totient is φ = 321525792.

The previous prime is 321618379. The next prime is 321618431. The reversal of 321618421 is 124816123.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 30404196 + 291214225 = 5514^2 + 17065^2 .

It is a cyclic number.

It is not a de Polignac number, because 321618421 - 2¹³ = 321610229 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 321618421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (321618431) 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, 40896 + ... + 48121.

It is an arithmetic number, because the mean of its divisors is an integer number (80427763).

Almost surely, 2^321618421 is an apocalyptic number.

It is an amenable number.

321618421 is a deficient number, since it is larger than the sum of its proper divisors (92631).

321618421 is an equidigital number, since it uses as much as digits as its factorization.

321618421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92630.

The product of its digits is 2304, while the sum is 28.

The square root of 321618421 is about 17933.7230100166. The cubic root of 321618421 is about 685.1415488824.

The spelling of 321618421 in words is "three hundred twenty-one million, six hundred eighteen thousand, four hundred twenty-one".