198564871 has 4 divisors (see below), whose sum is σ = 202311432. Its totient is φ = 194818312.

The previous prime is 198564869. The next prime is 198564901. The reversal of 198564871 is 178465891.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 178465891 = 607 ⋅294013.

It is a cyclic number.

It is not a de Polignac number, because 198564871 - 2¹ = 198564869 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (198564071) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1873201 + ... + 1873306.

It is an arithmetic number, because the mean of its divisors is an integer number (50577858).

Almost surely, 2^198564871 is an apocalyptic number.

198564871 is a deficient number, since it is larger than the sum of its proper divisors (3746561).

198564871 is an equidigital number, since it uses as much as digits as its factorization.

198564871 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3746560.

The product of its digits is 483840, while the sum is 49.

The square root of 198564871 is about 14091.3048011886. The cubic root of 198564871 is about 583.4014076383.

The spelling of 198564871 in words is "one hundred ninety-eight million, five hundred sixty-four thousand, eight hundred seventy-one".