320613731 has 2 divisors, whose sum is σ = 320613732. Its totient is φ = 320613730.

The previous prime is 320613707. The next prime is 320613739. The reversal of 320613731 is 137316023.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-320613731 is a prime.

It is a super-2 number, since 2×320613731² = 205586329011480722, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 320613731.

It is not a weakly prime, because it can be changed into another prime (320613739) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 160306865 + 160306866.

It is an arithmetic number, because the mean of its divisors is an integer number (160306866).

Almost surely, 2^320613731 is an apocalyptic number.

320613731 is a deficient number, since it is larger than the sum of its proper divisors (1).

320613731 is an equidigital number, since it uses as much as digits as its factorization.

320613731 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2268, while the sum is 26.

The square root of 320613731 is about 17905.6899057255. The cubic root of 320613731 is about 684.4273766020.

Adding to 320613731 its reverse (137316023), we get a palindrome (457929754).

The spelling of 320613731 in words is "three hundred twenty million, six hundred thirteen thousand, seven hundred thirty-one".