199218489 has 4 divisors (see below), whose sum is σ = 265624656. Its totient is φ = 132812324.

The previous prime is 199218469. The next prime is 199218499. The reversal of 199218489 is 984812991.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 199218489 - 2⁵ = 199218457 is a prime.

It is not an unprimeable number, because it can be changed into a prime (199218419) 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 3 ways as a sum of consecutive naturals, for example, 33203079 + ... + 33203084.

It is an arithmetic number, because the mean of its divisors is an integer number (66406164).

Almost surely, 2^199218489 is an apocalyptic number.

It is an amenable number.

199218489 is a deficient number, since it is larger than the sum of its proper divisors (66406167).

199218489 is an equidigital number, since it uses as much as digits as its factorization.

199218489 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66406166.

The product of its digits is 373248, while the sum is 51.

The square root of 199218489 is about 14114.4779924728. The cubic root of 199218489 is about 584.0408359901.

The spelling of 199218489 in words is "one hundred ninety-nine million, two hundred eighteen thousand, four hundred eighty-nine".