320240640 has 88 divisors (see below), whose sum is σ = 1024318800. Its totient is φ = 85393408.

The previous prime is 320240617. The next prime is 320240647. The reversal of 320240640 is 46042023.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (320240647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4936 + ... + 25784.

Almost surely, 2^320240640 is an apocalyptic number.

320240640 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 320240640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (512159400).

320240640 is an abundant number, since it is smaller than the sum of its proper divisors (704078160).

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

320240640 is a wasteful number, since it uses less digits than its factorization.

320240640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20877 (or 20859 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 21.

The square root of 320240640 is about 17895.2686484445. The cubic root of 320240640 is about 684.1617892992.

Adding to 320240640 its reverse (46042023), we get a palindrome (366282663).

The spelling of 320240640 in words is "three hundred twenty million, two hundred forty thousand, six hundred forty".