388665313 has 2 divisors, whose sum is σ = 388665314. Its totient is φ = 388665312.

The previous prime is 388665307. The next prime is 388665397. The reversal of 388665313 is 313566883.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 349577809 + 39087504 = 18697^2 + 6252^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-388665313 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 388665313.

It is not a weakly prime, because it can be changed into another prime (388665113) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 194332656 + 194332657.

It is an arithmetic number, because the mean of its divisors is an integer number (194332657).

Almost surely, 2^388665313 is an apocalyptic number.

It is an amenable number.

388665313 is a deficient number, since it is larger than the sum of its proper divisors (1).

388665313 is an equidigital number, since it uses as much as digits as its factorization.

388665313 is an evil number, because the sum of its binary digits is even.

The product of its digits is 311040, while the sum is 43.

The square root of 388665313 is about 19714.5964452737. The cubic root of 388665313 is about 729.7799505642.

The spelling of 388665313 in words is "three hundred eighty-eight million, six hundred sixty-five thousand, three hundred thirteen".