66125541667 has 4 divisors (see below), whose sum is σ = 66962573920. Its totient is φ = 65288509416.

The previous prime is 66125541611. The next prime is 66125541679. The reversal of 66125541667 is 76614552166.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 76614552166 = 2 ⋅38307276083.

It is a cyclic number.

It is not a de Polignac number, because 66125541667 - 2²⁷ = 65991323939 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 66125541667.

It is not an unprimeable number, because it can be changed into a prime (66125541607) 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, 418516008 + ... + 418516165.

It is an arithmetic number, because the mean of its divisors is an integer number (16740643480).

Almost surely, 2^66125541667 is an apocalyptic number.

66125541667 is a deficient number, since it is larger than the sum of its proper divisors (837032253).

66125541667 is an equidigital number, since it uses as much as digits as its factorization.

66125541667 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 837032252.

The product of its digits is 1814400, while the sum is 49.

The spelling of 66125541667 in words is "sixty-six billion, one hundred twenty-five million, five hundred forty-one thousand, six hundred sixty-seven".