198690971 has 2 divisors, whose sum is σ = 198690972. Its totient is φ = 198690970.

The previous prime is 198690959. The next prime is 198691007. The reversal of 198690971 is 179096891.

It is a weak prime.

It is an emirp because it is prime and its reverse (179096891) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 198690971 - 2¹⁰ = 198689947 is a prime.

It is not a weakly prime, because it can be changed into another prime (198690911) 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 as a sum of consecutive naturals, namely, 99345485 + 99345486.

It is an arithmetic number, because the mean of its divisors is an integer number (99345486).

Almost surely, 2^198690971 is an apocalyptic number.

198690971 is a deficient number, since it is larger than the sum of its proper divisors (1).

198690971 is an equidigital number, since it uses as much as digits as its factorization.

198690971 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 244944, while the sum is 50.

The square root of 198690971 is about 14095.7784815171. The cubic root of 198690971 is about 583.5248792097.

The spelling of 198690971 in words is "one hundred ninety-eight million, six hundred ninety thousand, nine hundred seventy-one".