643754248256 has 56 divisors (see below), whose sum is σ = 1460042450496. Its totient is φ = 275875822080.

The previous prime is 643754248231. The next prime is 643754248259. The reversal of 643754248256 is 652842457346.

It is a tau number, because it is divible by the number of its divisors (56).

It is a Harshad number since it is a multiple of its sum of digits (56).

It is not an unprimeable number, because it can be changed into a prime (643754248259) by changing a digit.

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, 7975010 + ... + 8055326.

It is an arithmetic number, because the mean of its divisors is an integer number (26072186616).

Almost surely, 2^643754248256 is an apocalyptic number.

It is an amenable number.

643754248256 is an abundant number, since it is smaller than the sum of its proper divisors (816288202240).

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

643754248256 is a wasteful number, since it uses less digits than its factorization.

643754248256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 98227 (or 98217 counting only the distinct ones).

The product of its digits is 38707200, while the sum is 56.

The spelling of 643754248256 in words is "six hundred forty-three billion, seven hundred fifty-four million, two hundred forty-eight thousand, two hundred fifty-six".