321600665 has 16 divisors (see below), whose sum is σ = 402333696. Its totient is φ = 246504000.

The previous prime is 321600659. The next prime is 321600683. The reversal of 321600665 is 566006123.

It is not a de Polignac number, because 321600665 - 2¹⁶ = 321535129 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5384 + ... + 25926.

It is an arithmetic number, because the mean of its divisors is an integer number (25145856).

Almost surely, 2^321600665 is an apocalyptic number.

It is an amenable number.

321600665 is a deficient number, since it is larger than the sum of its proper divisors (80733031).

321600665 is a wasteful number, since it uses less digits than its factorization.

321600665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20680.

The product of its (nonzero) digits is 6480, while the sum is 29.

The square root of 321600665 is about 17933.2279581786. The cubic root of 321600665 is about 685.1289401547.

Adding to 321600665 its reverse (566006123), we get a palindrome (887606788).

The spelling of 321600665 in words is "three hundred twenty-one million, six hundred thousand, six hundred sixty-five".