643198 has 8 divisors (see below), whose sum is σ = 971208. Its totient is φ = 319464.

The previous prime is 643187. The next prime is 643199. The reversal of 643198 is 891346.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 643198.

It is not an unprimeable number, because it can be changed into a prime (643199) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 661 + ... + 1312.

It is an arithmetic number, because the mean of its divisors is an integer number (121401).

2⁶⁴³¹⁹⁸ is an apocalyptic number.

643198 is a deficient number, since it is larger than the sum of its proper divisors (328010).

643198 is a wasteful number, since it uses less digits than its factorization.

643198 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2138.

The product of its digits is 5184, while the sum is 31.

The square root of 643198 is about 801.9962593429. The cubic root of 643198 is about 86.3206883915.

It can be divided in two parts, 643 and 198, that added together give a square (841 = 29²).

The spelling of 643198 in words is "six hundred forty-three thousand, one hundred ninety-eight".