643435 has 16 divisors (see below), whose sum is σ = 876960. Its totient is φ = 449280.

The previous prime is 643429. The next prime is 643439. The reversal of 643435 is 534346.

It is not a de Polignac number, because 643435 - 2⁵ = 643403 is a prime.

It is not an unprimeable number, because it can be changed into a prime (643439) 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 15 ways as a sum of consecutive naturals, for example, 975 + ... + 1495.

It is an arithmetic number, because the mean of its divisors is an integer number (54810).

2⁶⁴³⁴³⁵ is an apocalyptic number.

643435 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

643435 is a deficient number, since it is larger than the sum of its proper divisors (233525).

643435 is a wasteful number, since it uses less digits than its factorization.

643435 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 558.

The product of its digits is 4320, while the sum is 25.

The square root of 643435 is about 802.1440020345. The cubic root of 643435 is about 86.3312893215.

The spelling of 643435 in words is "six hundred forty-three thousand, four hundred thirty-five".