199889387 has 2 divisors, whose sum is σ = 199889388. Its totient is φ = 199889386.

The previous prime is 199889381. The next prime is 199889407. The reversal of 199889387 is 783988991.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-199889387 is a prime.

It is not a weakly prime, because it can be changed into another prime (199889381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99944693 + 99944694.

It is an arithmetic number, because the mean of its divisors is an integer number (99944694).

Almost surely, 2^199889387 is an apocalyptic number.

199889387 is a deficient number, since it is larger than the sum of its proper divisors (1).

199889387 is an equidigital number, since it uses as much as digits as its factorization.

199889387 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7838208, while the sum is 62.

The square root of 199889387 is about 14138.2243227359. The cubic root of 199889387 is about 584.6957163029.

The spelling of 199889387 in words is "one hundred ninety-nine million, eight hundred eighty-nine thousand, three hundred eighty-seven".