318728617 has 2 divisors, whose sum is σ = 318728618. Its totient is φ = 318728616.

The previous prime is 318728609. The next prime is 318728621. The reversal of 318728617 is 716827813.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 162078361 + 156650256 = 12731^2 + 12516^2 .

It is a cyclic number.

It is not a de Polignac number, because 318728617 - 2³ = 318728609 is a prime.

It is a super-3 number, since 3×318728617³ (a number of 26 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (318728717) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 159364308 + 159364309.

It is an arithmetic number, because the mean of its divisors is an integer number (159364309).

Almost surely, 2^318728617 is an apocalyptic number.

It is an amenable number.

318728617 is a deficient number, since it is larger than the sum of its proper divisors (1).

318728617 is an equidigital number, since it uses as much as digits as its factorization.

318728617 is an evil number, because the sum of its binary digits is even.

The product of its digits is 112896, while the sum is 43.

The square root of 318728617 is about 17852.9722175329. The cubic root of 318728617 is about 683.0833287043.

The spelling of 318728617 in words is "three hundred eighteen million, seven hundred twenty-eight thousand, six hundred seventeen".