199961903242 has 16 divisors (see below), whose sum is σ = 304068120840. Its totient is φ = 98606011392.

The previous prime is 199961903171. The next prime is 199961903257. The reversal of 199961903242 is 242309169991.

It is a Cunningham number, because it is equal to 447171²+1.

It can be written as a sum of positive squares in 4 ways, for example, as 199961903241 + 1 = 447171^2 + 1^2 .

It is a super-2 number, since 2×199961903242² (a number of 23 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5077684 + ... + 5116912.

Almost surely, 2^199961903242 is an apocalyptic number.

199961903242 is a deficient number, since it is larger than the sum of its proper divisors (104106217598).

199961903242 is a wasteful number, since it uses less digits than its factorization.

199961903242 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74217.

The product of its (nonzero) digits is 1889568, while the sum is 55.

The spelling of 199961903242 in words is "one hundred ninety-nine billion, nine hundred sixty-one million, nine hundred three thousand, two hundred forty-two".