320138560 has 168 divisors, whose sum is σ = 939738024. Its totient is φ = 103219200.

The previous prime is 320138549. The next prime is 320138561. The reversal of 320138560 is 65831023.

It can be written as a sum of positive squares in 4 ways, for example, as 3013696 + 317124864 = 1736^2 + 17808^2 .

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (320138561) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 265960 + ... + 267160.

Almost surely, 2^320138560 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 320138560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (469869012).

320138560 is an abundant number, since it is smaller than the sum of its proper divisors (619599464).

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

320138560 is a wasteful number, since it uses less digits than its factorization.

320138560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1249 (or 1232 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 28.

The square root of 320138560 is about 17892.4162705879. The cubic root of 320138560 is about 684.0890870365.

Adding to 320138560 its reverse (65831023), we get a palindrome (385969583).

The spelling of 320138560 in words is "three hundred twenty million, one hundred thirty-eight thousand, five hundred sixty".