199724117 has 2 divisors, whose sum is σ = 199724118. Its totient is φ = 199724116.

The previous prime is 199724059. The next prime is 199724149. The reversal of 199724117 is 711427991.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 195748081 + 3976036 = 13991^2 + 1994^2 .

It is a cyclic number.

It is not a de Polignac number, because 199724117 - 2⁶ = 199724053 is a prime.

It is a super-2 number, since 2×199724117² = 79779445822859378, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (199724017) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99862058 + 99862059.

It is an arithmetic number, because the mean of its divisors is an integer number (99862059).

Almost surely, 2^199724117 is an apocalyptic number.

It is an amenable number.

199724117 is a deficient number, since it is larger than the sum of its proper divisors (1).

199724117 is an equidigital number, since it uses as much as digits as its factorization.

199724117 is an evil number, because the sum of its binary digits is even.

The product of its digits is 31752, while the sum is 41.

The square root of 199724117 is about 14132.3783207215. The cubic root of 199724117 is about 584.5345283130.

The spelling of 199724117 in words is "one hundred ninety-nine million, seven hundred twenty-four thousand, one hundred seventeen".