198626891 has 4 divisors (see below), whose sum is σ = 198778800. Its totient is φ = 198474984.

The previous prime is 198626849. The next prime is 198626899.

It is a happy number.

198626891 is nontrivially palindromic in base 10.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-198626891 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (198626899) 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 3 ways as a sum of consecutive naturals, for example, 73976 + ... + 76613.

It is an arithmetic number, because the mean of its divisors is an integer number (49694700).

Almost surely, 2^198626891 is an apocalyptic number.

198626891 is a deficient number, since it is larger than the sum of its proper divisors (151909).

198626891 is a wasteful number, since it uses less digits than its factorization.

198626891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 151908.

The product of its digits is 373248, while the sum is 50.

The square root of 198626891 is about 14093.5052772545. The cubic root of 198626891 is about 583.4621414238.

The spelling of 198626891 in words is "one hundred ninety-eight million, six hundred twenty-six thousand, eight hundred ninety-one".