643476959 has 8 divisors (see below), whose sum is σ = 650825280. Its totient is φ = 636148000.

The previous prime is 643476941. The next prime is 643476961. The reversal of 643476959 is 959674346.

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

It is a cyclic number.

It is not a de Polignac number, because 643476959 - 2¹⁶ = 643411423 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 643476959.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643476929) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 68189 + ... + 77049.

It is an arithmetic number, because the mean of its divisors is an integer number (81353160).

Almost surely, 2^643476959 is an apocalyptic number.

643476959 is a deficient number, since it is larger than the sum of its proper divisors (7348321).

643476959 is a wasteful number, since it uses less digits than its factorization.

643476959 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9681.

The product of its digits is 4898880, while the sum is 53.

The square root of 643476959 is about 25366.8476362358. The cubic root of 643476959 is about 863.3316586217.

The spelling of 643476959 in words is "six hundred forty-three million, four hundred seventy-six thousand, nine hundred fifty-nine".