643562 has 8 divisors (see below), whose sum is σ = 972192. Its totient is φ = 319500.

The previous prime is 643553. The next prime is 643567. The reversal of 643562 is 265346.

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

It is a nialpdrome in base 15.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 643562.

It is not an unprimeable number, because it can be changed into a prime (643567) 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, 764 + ... + 1367.

It is an arithmetic number, because the mean of its divisors is an integer number (121524).

2⁶⁴³⁵⁶² is an apocalyptic number.

643562 is a deficient number, since it is larger than the sum of its proper divisors (328630).

643562 is a wasteful number, since it uses less digits than its factorization.

643562 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2284.

The product of its digits is 4320, while the sum is 26.

The square root of 643562 is about 802.2231609721. The cubic root of 643562 is about 86.3369689175.

The spelling of 643562 in words is "six hundred forty-three thousand, five hundred sixty-two".