198754457891 has 8 divisors (see below), whose sum is σ = 221436301824. Its totient is φ = 176841490120.

The previous prime is 198754457851. The next prime is 198754457921.

198754457891 is nontrivially palindromic in base 10.

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

It is a cyclic number.

It is not a de Polignac number, because 198754457891 - 2¹⁰ = 198754456867 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (198754457801) 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, 192218495 + ... + 192219528.

It is an arithmetic number, because the mean of its divisors is an integer number (27679537728).

Almost surely, 2^198754457891 is an apocalyptic number.

198754457891 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

198754457891 is a deficient number, since it is larger than the sum of its proper divisors (22681843933).

198754457891 is a wasteful number, since it uses less digits than its factorization.

198754457891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 384438081.

The product of its digits is 101606400, while the sum is 68.

The spelling of 198754457891 in words is "one hundred ninety-eight billion, seven hundred fifty-four million, four hundred fifty-seven thousand, eight hundred ninety-one".