6543905811 has 4 divisors (see below), whose sum is σ = 8725207752. Its totient is φ = 4362603872.

The previous prime is 6543905783. The next prime is 6543905821. The reversal of 6543905811 is 1185093456.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 6543905811 - 2⁵ = 6543905779 is a prime.

It is not an unprimeable number, because it can be changed into a prime (6543905821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1090650966 + ... + 1090650971.

It is an arithmetic number, because the mean of its divisors is an integer number (2181301938).

Almost surely, 2^6543905811 is an apocalyptic number.

6543905811 is a deficient number, since it is larger than the sum of its proper divisors (2181301941).

6543905811 is a wasteful number, since it uses less digits than its factorization.

6543905811 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2181301940.

The product of its (nonzero) digits is 129600, while the sum is 42.

The square root of 6543905811 is about 80894.4114942435. The cubic root of 6543905811 is about 1870.4481763918.

The spelling of 6543905811 in words is "six billion, five hundred forty-three million, nine hundred five thousand, eight hundred eleven".