643561087041 has 24 divisors (see below), whose sum is σ = 955069406720. Its totient is φ = 417288861216.

The previous prime is 643561086997. The next prime is 643561087063. The reversal of 643561087041 is 140780165346.

643561087041 is a `hidden beast` number, since 6 + 4 + 3 + 561 + 0 + 87 + 0 + 4 + 1 = 666.

It is not a de Polignac number, because 643561087041 - 2¹⁵ = 643561054273 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (643561087541) 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 23 ways as a sum of consecutive naturals, for example, 533280 + ... + 1253598.

Almost surely, 2^643561087041 is an apocalyptic number.

It is an amenable number.

643561087041 is a deficient number, since it is larger than the sum of its proper divisors (311508319679).

643561087041 is a wasteful number, since it uses less digits than its factorization.

643561087041 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 723045 (or 723042 counting only the distinct ones).

The product of its (nonzero) digits is 483840, while the sum is 45.

The spelling of 643561087041 in words is "six hundred forty-three billion, five hundred sixty-one million, eighty-seven thousand, forty-one".