329812321 has 4 divisors (see below), whose sum is σ = 334330372. Its totient is φ = 325294272.

The previous prime is 329812297. The next prime is 329812337. The reversal of 329812321 is 123218923.

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 62980096 + 266832225 = 7936^2 + 16335^2 .

It is a cyclic number.

It is not a de Polignac number, because 329812321 - 2¹³ = 329804129 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (329812381) 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, 2258916 + ... + 2259061.

It is an arithmetic number, because the mean of its divisors is an integer number (83582593).

Almost surely, 2^329812321 is an apocalyptic number.

It is an amenable number.

329812321 is a deficient number, since it is larger than the sum of its proper divisors (4518051).

329812321 is an equidigital number, since it uses as much as digits as its factorization.

329812321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4518050.

The product of its digits is 5184, while the sum is 31.

The square root of 329812321 is about 18160.7356954502. The cubic root of 329812321 is about 690.9112939843.

The spelling of 329812321 in words is "three hundred twenty-nine million, eight hundred twelve thousand, three hundred twenty-one".