643779412792 has 32 divisors (see below), whose sum is σ = 1258361596800. Its totient is φ = 308421936000.

The previous prime is 643779412751. The next prime is 643779412831. The reversal of 643779412792 is 297214977346.

It is a self number, because there is not a number n which added to its sum of digits gives 643779412792.

It is a congruent number.

It is an unprimeable number.

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, 12825867 + ... + 12875962.

It is an arithmetic number, because the mean of its divisors is an integer number (39323799900).

Almost surely, 2^643779412792 is an apocalyptic number.

643779412792 is a gapful number since it is divisible by the number (62) formed by its first and last digit.

It is an amenable number.

643779412792 is a deficient number, since it is larger than the sum of its proper divisors (614582184008).

643779412792 is a wasteful number, since it uses less digits than its factorization.

643779412792 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25701967 (or 25701963 counting only the distinct ones).

The product of its digits is 32006016, while the sum is 61.

The spelling of 643779412792 in words is "six hundred forty-three billion, seven hundred seventy-nine million, four hundred twelve thousand, seven hundred ninety-two".