388394891 has 2 divisors, whose sum is σ = 388394892. Its totient is φ = 388394890.

The previous prime is 388394879. The next prime is 388394893. The reversal of 388394891 is 198493883.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-388394891 is a prime.

Together with 388394893, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (388394893) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 194197445 + 194197446.

It is an arithmetic number, because the mean of its divisors is an integer number (194197446).

Almost surely, 2^388394891 is an apocalyptic number.

388394891 is a deficient number, since it is larger than the sum of its proper divisors (1).

388394891 is an equidigital number, since it uses as much as digits as its factorization.

388394891 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1492992, while the sum is 53.

The square root of 388394891 is about 19707.7368310012. The cubic root of 388394891 is about 729.6106580867.

The spelling of 388394891 in words is "three hundred eighty-eight million, three hundred ninety-four thousand, eight hundred ninety-one".