321616 has 10 divisors (see below), whose sum is σ = 623162. Its totient is φ = 160800.

The previous prime is 321611. The next prime is 321617. The reversal of 321616 is 616123.

It can be written as a sum of positive squares in only one way, i.e., 254016 + 67600 = 504^2 + 260^2 .

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

321616 is a modest number, since divided by 1616 gives 32 as remainder.

It is a junction number, because it is equal to n+sod(n) for n = 321593 and 321602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (321611) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10035 + ... + 10066.

2³²¹⁶¹⁶ is an apocalyptic number.

It is an amenable number.

321616 is a deficient number, since it is larger than the sum of its proper divisors (301546).

321616 is a wasteful number, since it uses less digits than its factorization.

321616 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20109 (or 20103 counting only the distinct ones).

The product of its digits is 216, while the sum is 19.

The square root of 321616 is about 567.1119818872. Note that the first 3 decimals coincide. The cubic root of 321616 is about 68.5139829731.

Adding to 321616 its reverse (616123), we get a palindrome (937739).

The spelling of 321616 in words is "three hundred twenty-one thousand, six hundred sixteen".