66538844065 has 8 divisors (see below), whose sum is σ = 79848816768. Its totient is φ = 53229606000.

The previous prime is 66538844051. The next prime is 66538844107. The reversal of 66538844065 is 56044883566.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 66538844065 - 2²⁵ = 66505289633 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 66538843997 and 66538844015.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 40474 + ... + 367036.

It is an arithmetic number, because the mean of its divisors is an integer number (9981102096).

Almost surely, 2^66538844065 is an apocalyptic number.

It is an amenable number.

66538844065 is a deficient number, since it is larger than the sum of its proper divisors (13309972703).

66538844065 is a wasteful number, since it uses less digits than its factorization.

66538844065 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 367319.

The product of its (nonzero) digits is 16588800, while the sum is 55.

The spelling of 66538844065 in words is "sixty-six billion, five hundred thirty-eight million, eight hundred forty-four thousand, sixty-five".