199801807 has 2 divisors, whose sum is σ = 199801808. Its totient is φ = 199801806.

The previous prime is 199801801. The next prime is 199801831. The reversal of 199801807 is 708108991.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 199801807 - 2¹⁵ = 199769039 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (199801801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99900903 + 99900904.

It is an arithmetic number, because the mean of its divisors is an integer number (99900904).

Almost surely, 2^199801807 is an apocalyptic number.

199801807 is a deficient number, since it is larger than the sum of its proper divisors (1).

199801807 is an equidigital number, since it uses as much as digits as its factorization.

199801807 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 36288, while the sum is 43.

The square root of 199801807 is about 14135.1267061884. The cubic root of 199801807 is about 584.6103105156.

The spelling of 199801807 in words is "one hundred ninety-nine million, eight hundred one thousand, eight hundred seven".