643353 has 4 divisors (see below), whose sum is σ = 857808. Its totient is φ = 428900.

The previous prime is 643303. The next prime is 643369. The reversal of 643353 is 353346.

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 643353 - 2¹² = 639257 is a prime.

It is a D-number.

It is a Curzon number.

It is a nialpdrome in base 15.

It is not an unprimeable number, because it can be changed into a prime (643303) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 107223 + ... + 107228.

It is an arithmetic number, because the mean of its divisors is an integer number (214452).

2⁶⁴³³⁵³ is an apocalyptic number.

It is an amenable number.

643353 is a deficient number, since it is larger than the sum of its proper divisors (214455).

643353 is a wasteful number, since it uses less digits than its factorization.

643353 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 214454.

The product of its digits is 3240, while the sum is 24.

The square root of 643353 is about 802.0928873890. The cubic root of 643353 is about 86.3276217837.

Adding to 643353 its reverse (353346), we get a palindrome (996699).

The spelling of 643353 in words is "six hundred forty-three thousand, three hundred fifty-three".