399120187 has 2 divisors, whose sum is σ = 399120188. Its totient is φ = 399120186.

The previous prime is 399120179. The next prime is 399120217. The reversal of 399120187 is 781021993.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 399120187 - 2³ = 399120179 is a prime.

It is not a weakly prime, because it can be changed into another prime (399120107) 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, 199560093 + 199560094.

It is an arithmetic number, because the mean of its divisors is an integer number (199560094).

Almost surely, 2^399120187 is an apocalyptic number.

399120187 is a deficient number, since it is larger than the sum of its proper divisors (1).

399120187 is an equidigital number, since it uses as much as digits as its factorization.

399120187 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 27216, while the sum is 40.

The square root of 399120187 is about 19977.9925668221. The cubic root of 399120187 is about 736.2656933729.

The spelling of 399120187 in words is "three hundred ninety-nine million, one hundred twenty thousand, one hundred eighty-seven".