321330640 has 40 divisors (see below), whose sum is σ = 750922920. Its totient is φ = 127873536.

The previous prime is 321330637. The next prime is 321330649. The reversal of 321330640 is 46033123.

It can be written as a sum of positive squares in 4 ways, for example, as 206669376 + 114661264 = 14376^2 + 10708^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (321330649) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5566 + ... + 25954.

It is an arithmetic number, because the mean of its divisors is an integer number (18773073).

Almost surely, 2^321330640 is an apocalyptic number.

It is an amenable number.

321330640 is an abundant number, since it is smaller than the sum of its proper divisors (429592280).

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

321330640 is a wasteful number, since it uses less digits than its factorization.

321330640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20599 (or 20593 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 22.

The square root of 321330640 is about 17925.6977548992. The cubic root of 321330640 is about 684.9371352613.

Adding to 321330640 its reverse (46033123), we get a palindrome (367363763).

The spelling of 321330640 in words is "three hundred twenty-one million, three hundred thirty thousand, six hundred forty".