321040 has 20 divisors (see below), whose sum is σ = 746604. Its totient is φ = 128384.

The previous prime is 321037. The next prime is 321047. The reversal of 321040 is 40123.

It can be written as a sum of positive squares in 2 ways, for example, as 197136 + 123904 = 444^2 + 352^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a Harshad number since it is a multiple of its sum of digits (10).

It is an Ulam number.

It is not an unprimeable number, because it can be changed into a prime (321047) 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 in 3 ways as a sum of consecutive naturals, for example, 1927 + ... + 2086.

2³²¹⁰⁴⁰ is an apocalyptic number.

It is an amenable number.

321040 is an abundant number, since it is smaller than the sum of its proper divisors (425564).

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

321040 is a wasteful number, since it uses less digits than its factorization.

321040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4026 (or 4020 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 10.

The square root of 321040 is about 566.6039180945. The cubic root of 321040 is about 68.4730566955.

Adding to 321040 its reverse (40123), we get a palindrome (361163).

The spelling of 321040 in words is "three hundred twenty-one thousand, forty", and thus it is an iban number.