198023771 has 4 divisors (see below), whose sum is σ = 216025944. Its totient is φ = 180021600.

The previous prime is 198023759. The next prime is 198023789. The reversal of 198023771 is 177320891.

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

It is a de Polignac number, because none of the positive numbers 2^k-198023771 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (198029771) 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, 9001070 + ... + 9001091.

It is an arithmetic number, because the mean of its divisors is an integer number (54006486).

Almost surely, 2^198023771 is an apocalyptic number.

198023771 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

198023771 is a deficient number, since it is larger than the sum of its proper divisors (18002173).

198023771 is a wasteful number, since it uses less digits than its factorization.

198023771 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18002172.

The product of its (nonzero) digits is 21168, while the sum is 38.

The square root of 198023771 is about 14072.0919198249. The cubic root of 198023771 is about 582.8709920920.

The spelling of 198023771 in words is "one hundred ninety-eight million, twenty-three thousand, seven hundred seventy-one".