321620 has 24 divisors (see below), whose sum is σ = 727944. Its totient is φ = 118656.

The previous prime is 321619. The next prime is 321631. The reversal of 321620 is 26123.

It can be written as a sum of positive squares in 4 ways, for example, as 21316 + 300304 = 146^2 + 548^2 .

It is a junction number, because it is equal to n+sod(n) for n = 321595 and 321604.

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 321620.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 359 + ... + 878.

It is an arithmetic number, because the mean of its divisors is an integer number (30331).

2³²¹⁶²⁰ is an apocalyptic number.

It is an amenable number.

321620 is an abundant number, since it is smaller than the sum of its proper divisors (406324).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

321620 is a wasteful number, since it uses less digits than its factorization.

321620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1259 (or 1257 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 14.

The square root of 321620 is about 567.1155085166. The cubic root of 321620 is about 68.5142670125.

Adding to 321620 its reverse (26123), we get a palindrome (347743).

The spelling of 321620 in words is "three hundred twenty-one thousand, six hundred twenty".