643312735 has 32 divisors (see below), whose sum is σ = 893813760. Its totient is φ = 440443008.

The previous prime is 643312687. The next prime is 643312739. The reversal of 643312735 is 537213346.

643312735 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 643312735 - 2¹¹ = 643310687 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 643312735.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643312739) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 52504 + ... + 63586.

It is an arithmetic number, because the mean of its divisors is an integer number (27931680).

Almost surely, 2^643312735 is an apocalyptic number.

643312735 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

643312735 is a deficient number, since it is larger than the sum of its proper divisors (250501025).

643312735 is a wasteful number, since it uses less digits than its factorization.

643312735 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11167.

The product of its digits is 45360, while the sum is 34.

The square root of 643312735 is about 25363.6104488300. The cubic root of 643312735 is about 863.2582077445.

The spelling of 643312735 in words is "six hundred forty-three million, three hundred twelve thousand, seven hundred thirty-five".