321901609 has 4 divisors (see below), whose sum is σ = 322187860. Its totient is φ = 321615360.

The previous prime is 321901523. The next prime is 321901651. The reversal of 321901609 is 906109123.

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 20115225 + 301786384 = 4485^2 + 17372^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-321901609 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (321901709) 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, 141432 + ... + 143689.

It is an arithmetic number, because the mean of its divisors is an integer number (80546965).

Almost surely, 2^321901609 is an apocalyptic number.

It is an amenable number.

321901609 is a deficient number, since it is larger than the sum of its proper divisors (286251).

321901609 is a wasteful number, since it uses less digits than its factorization.

321901609 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 286250.

The product of its (nonzero) digits is 2916, while the sum is 31.

The square root of 321901609 is about 17941.6166774346. The cubic root of 321901609 is about 685.3425810513.

It can be divided in two parts, 32 and 1901609, that added together give a square (1901641 = 1379²).

The spelling of 321901609 in words is "three hundred twenty-one million, nine hundred one thousand, six hundred nine".