643565346 has 32 divisors (see below), whose sum is σ = 1379403648. Its totient is φ = 199647360.

The previous prime is 643565291. The next prime is 643565347.

It is a happy number.

643565346 is nontrivially palindromic in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 643565298 and 643565307.

It is not an unprimeable number, because it can be changed into a prime (643565347) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 57915 + ... + 68126.

It is an arithmetic number, because the mean of its divisors is an integer number (43106364).

Almost surely, 2^643565346 is an apocalyptic number.

643565346 is an abundant number, since it is smaller than the sum of its proper divisors (735838302).

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

643565346 is a wasteful number, since it uses less digits than its factorization.

643565346 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 126106.

The product of its digits is 777600, while the sum is 42.

The square root of 643565346 is about 25368.5897518959. The cubic root of 643565346 is about 863.3711854459.

The spelling of 643565346 in words is "six hundred forty-three million, five hundred sixty-five thousand, three hundred forty-six".