643512265 has 8 divisors (see below), whose sum is σ = 842416128. Its totient is φ = 468008880.

The previous prime is 643512253. The next prime is 643512281. The reversal of 643512265 is 562215346.

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

It is not a de Polignac number, because 643512265 - 2⁷ = 643512137 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 643512265.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5850057 + ... + 5850166.

It is an arithmetic number, because the mean of its divisors is an integer number (105302016).

Almost surely, 2^643512265 is an apocalyptic number.

It is an amenable number.

643512265 is a deficient number, since it is larger than the sum of its proper divisors (198903863).

643512265 is a wasteful number, since it uses less digits than its factorization.

643512265 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11700239.

The product of its digits is 43200, while the sum is 34.

The square root of 643512265 is about 25367.5435349976. The cubic root of 643512265 is about 863.3474479621.

The spelling of 643512265 in words is "six hundred forty-three million, five hundred twelve thousand, two hundred sixty-five".