320013505 has 16 divisors (see below), whose sum is σ = 442085760. Its totient is φ = 217832832.

The previous prime is 320013479. The next prime is 320013509. The reversal of 320013505 is 505310023.

It is a Cunningham number, because it is equal to 684³+1.

It is not a de Polignac number, because 320013505 - 2⁷ = 320013377 is a prime.

It is not an unprimeable number, because it can be changed into a prime (320013509) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 28575 + ... + 38164.

It is an arithmetic number, because the mean of its divisors is an integer number (27630360).

Almost surely, 2^320013505 is an apocalyptic number.

320013505 is a gapful number since it is divisible by the number (35) formed by its first and last digit.

It is an amenable number.

320013505 is a deficient number, since it is larger than the sum of its proper divisors (122072255).

320013505 is a wasteful number, since it uses less digits than its factorization.

320013505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66888.

The product of its (nonzero) digits is 450, while the sum is 19.

The square root of 320013505 is about 17888.9212922412. The cubic root of 320013505 is about 684.0000007125. Note that the first 6 decimals are identical.

Adding to 320013505 its reverse (505310023), we get a palindrome (825323528).

The spelling of 320013505 in words is "three hundred twenty million, thirteen thousand, five hundred five".