199999979740125 has 108 divisors (see below), whose sum is σ = 368408495712348. Its totient is φ = 104385515364000.

The previous prime is 199999979740073. The next prime is 199999979740163. The reversal of 199999979740125 is 521047979999991.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

199999979740125 is a `hidden beast` number, since 1 + 9 + 9 + 9 + 9 + 9 + 97 + 97 + 401 + 25 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 6399999351684 + 193599980388441 = 2529822^2 + 13914021^2 .

It is not a de Polignac number, because 199999979740125 - 2¹⁰ = 199999979739101 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 107 ways as a sum of consecutive naturals, for example, 22294051890 + ... + 22294060860.

Almost surely, 2^{199999979740125} is an apocalyptic number.

199999979740125 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

199999979740125 is a deficient number, since it is larger than the sum of its proper divisors (168408515972223).

199999979740125 is an frugal number, since it uses more digits than its factorization.

199999979740125 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18057 (or 9026 counting only the distinct ones).

The product of its (nonzero) digits is 9374619240, while the sum is 90.

The spelling of 199999979740125 in words is "one hundred ninety-nine trillion, nine hundred ninety-nine billion, nine hundred seventy-nine million, seven hundred forty thousand, one hundred twenty-five".