199718479 has 2 divisors, whose sum is σ = 199718480. Its totient is φ = 199718478.

The previous prime is 199718471. The next prime is 199718507. The reversal of 199718479 is 974817991.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 199718479 - 2³ = 199718471 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (199718471) 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, 99859239 + 99859240.

It is an arithmetic number, because the mean of its divisors is an integer number (99859240).

Almost surely, 2^199718479 is an apocalyptic number.

199718479 is a deficient number, since it is larger than the sum of its proper divisors (1).

199718479 is an equidigital number, since it uses as much as digits as its factorization.

199718479 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1143072, while the sum is 55.

The square root of 199718479 is about 14132.1788482880. The cubic root of 199718479 is about 584.5290279980.

The spelling of 199718479 in words is "one hundred ninety-nine million, seven hundred eighteen thousand, four hundred seventy-nine".