199730123 has 2 divisors, whose sum is σ = 199730124. Its totient is φ = 199730122.

The previous prime is 199730053. The next prime is 199730143. The reversal of 199730123 is 321037991.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 199730123 - 2⁸ = 199729867 is a prime.

It is not a weakly prime, because it can be changed into another prime (199730143) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99865061 + 99865062.

It is an arithmetic number, because the mean of its divisors is an integer number (99865062).

Almost surely, 2^199730123 is an apocalyptic number.

199730123 is a deficient number, since it is larger than the sum of its proper divisors (1).

199730123 is an equidigital number, since it uses as much as digits as its factorization.

199730123 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10206, while the sum is 35.

The square root of 199730123 is about 14132.5908098975. The cubic root of 199730123 is about 584.5403875272.

The spelling of 199730123 in words is "one hundred ninety-nine million, seven hundred thirty thousand, one hundred twenty-three".