643398 has 16 divisors (see below), whose sum is σ = 1470720. Its totient is φ = 183816.

The previous prime is 643373. The next prime is 643403. The reversal of 643398 is 893346.

It is a Curzon number.

It is a nialpdrome in base 15.

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 643398.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7618 + ... + 7701.

It is an arithmetic number, because the mean of its divisors is an integer number (91920).

2⁶⁴³³⁹⁸ is an apocalyptic number.

643398 is an abundant number, since it is smaller than the sum of its proper divisors (827322).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

643398 is a wasteful number, since it uses less digits than its factorization.

643398 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15331.

The product of its digits is 15552, while the sum is 33.

The square root of 643398 is about 802.1209385124. The cubic root of 643398 is about 86.3296344955.

The spelling of 643398 in words is "six hundred forty-three thousand, three hundred ninety-eight".