199485991 has 2 divisors, whose sum is σ = 199485992. Its totient is φ = 199485990.

The previous prime is 199485967. The next prime is 199486031. The reversal of 199485991 is 199584991.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 199485991 - 2⁹ = 199485479 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (199485491) 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, 99742995 + 99742996.

It is an arithmetic number, because the mean of its divisors is an integer number (99742996).

Almost surely, 2^199485991 is an apocalyptic number.

199485991 is a deficient number, since it is larger than the sum of its proper divisors (1).

199485991 is an equidigital number, since it uses as much as digits as its factorization.

199485991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1049760, while the sum is 55.

The square root of 199485991 is about 14123.9509698951. The cubic root of 199485991 is about 584.3021273615.

The spelling of 199485991 in words is "one hundred ninety-nine million, four hundred eighty-five thousand, nine hundred ninety-one".