199999955 has 8 divisors (see below), whose sum is σ = 243038400. Its totient is φ = 157974336.

The previous prime is 199999949. The next prime is 199999957. The reversal of 199999955 is 559999991.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-199999955 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 199999891 and 199999900.

It is not an unprimeable number, because it can be changed into a prime (199999957) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 252770 + ... + 253559.

It is an arithmetic number, because the mean of its divisors is an integer number (30379800).

Almost surely, 2^199999955 is an apocalyptic number.

199999955 is a deficient number, since it is larger than the sum of its proper divisors (43038445).

199999955 is an equidigital number, since it uses as much as digits as its factorization.

199999955 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 506413.

The product of its digits is 13286025, while the sum is 65.

The square root of 199999955 is about 14142.1340327406. The cubic root of 199999955 is about 584.8035037823.

It can be divided in two parts, 1999 and 99955, that multiplied together give a triangular number (199810045 = T₁₉₉₉₀).

The spelling of 199999955 in words is "one hundred ninety-nine million, nine hundred ninety-nine thousand, nine hundred fifty-five".