198171587 has 8 divisors (see below), whose sum is σ = 205233600. Its totient is φ = 191124864.

The previous prime is 198171581. The next prime is 198171607. The reversal of 198171587 is 785171891.

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 198171587 - 2¹⁰ = 198170563 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (198171581) 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 7 ways as a sum of consecutive naturals, for example, 26843 + ... + 33419.

It is an arithmetic number, because the mean of its divisors is an integer number (25654200).

Almost surely, 2^198171587 is an apocalyptic number.

198171587 is a deficient number, since it is larger than the sum of its proper divisors (7062013).

198171587 is a wasteful number, since it uses less digits than its factorization.

198171587 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7645.

The product of its digits is 141120, while the sum is 47.

The square root of 198171587 is about 14077.3430376616. The cubic root of 198171587 is about 583.0159851727.

The spelling of 198171587 in words is "one hundred ninety-eight million, one hundred seventy-one thousand, five hundred eighty-seven".