643787243597 has 4 divisors (see below), whose sum is σ = 644174369280. Its totient is φ = 643400117916.

The previous prime is 643787243581. The next prime is 643787243611. The reversal of 643787243597 is 795342787346.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 643787243597 - 2⁴ = 643787243581 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643787243497) 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 3 ways as a sum of consecutive naturals, for example, 193560347 + ... + 193563672.

It is an arithmetic number, because the mean of its divisors is an integer number (161043592320).

Almost surely, 2^643787243597 is an apocalyptic number.

It is an amenable number.

643787243597 is a deficient number, since it is larger than the sum of its proper divisors (387125683).

643787243597 is a wasteful number, since it uses less digits than its factorization.

643787243597 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 387125682.

The product of its digits is 213373440, while the sum is 65.

The spelling of 643787243597 in words is "six hundred forty-three billion, seven hundred eighty-seven million, two hundred forty-three thousand, five hundred ninety-seven".