199118639 has 4 divisors (see below), whose sum is σ = 199148880. Its totient is φ = 199088400.

The previous prime is 199118629. The next prime is 199118723. The reversal of 199118639 is 936811991.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 936811991 = 37 ⋅25319243.

It is a cyclic number.

It is not a de Polignac number, because 199118639 - 2¹² = 199114543 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 199118593 and 199118602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (199118629) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 587 + ... + 19964.

It is an arithmetic number, because the mean of its divisors is an integer number (49787220).

Almost surely, 2^199118639 is an apocalyptic number.

199118639 is a deficient number, since it is larger than the sum of its proper divisors (30241).

199118639 is an equidigital number, since it uses as much as digits as its factorization.

199118639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30240.

The product of its digits is 104976, while the sum is 47.

The square root of 199118639 is about 14110.9404009797. The cubic root of 199118639 is about 583.9432442733.

The spelling of 199118639 in words is "one hundred ninety-nine million, one hundred eighteen thousand, six hundred thirty-nine".