321638 has 8 divisors (see below), whose sum is σ = 489288. Its totient is φ = 158544.

The previous prime is 321631. The next prime is 321647. The reversal of 321638 is 836123.

It is a sphenic number, since it is the product of 3 distinct primes.

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

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 321638.

It is not an unprimeable number, because it can be changed into a prime (321631) 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, 956 + ... + 1247.

It is an arithmetic number, because the mean of its divisors is an integer number (61161).

2³²¹⁶³⁸ is an apocalyptic number.

321638 is a deficient number, since it is larger than the sum of its proper divisors (167650).

321638 is a wasteful number, since it uses less digits than its factorization.

321638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2278.

The product of its digits is 864, while the sum is 23.

The square root of 321638 is about 567.1313780774. The cubic root of 321638 is about 68.5155451604.

It can be divided in two parts, 321 and 638, that added together give a palindrome (959).

The spelling of 321638 in words is "three hundred twenty-one thousand, six hundred thirty-eight".