389193991 has 2 divisors, whose sum is σ = 389193992. Its totient is φ = 389193990.

The previous prime is 389193977. The next prime is 389194019. The reversal of 389193991 is 199391983.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 389193991 - 2⁹ = 389193479 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (389193911) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 194596995 + 194596996.

It is an arithmetic number, because the mean of its divisors is an integer number (194596996).

Almost surely, 2^389193991 is an apocalyptic number.

389193991 is a deficient number, since it is larger than the sum of its proper divisors (1).

389193991 is an equidigital number, since it uses as much as digits as its factorization.

389193991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 472392, while the sum is 52.

The square root of 389193991 is about 19728.0001774128. Note that the first 3 decimals coincide. The cubic root of 389193991 is about 730.1106925408.

The spelling of 389193991 in words is "three hundred eighty-nine million, one hundred ninety-three thousand, nine hundred ninety-one".