66001615705 has 12 divisors (see below), whose sum is σ = 81180819756. Its totient is φ = 51513449600.

The previous prime is 66001615703. The next prime is 66001615723. The reversal of 66001615705 is 50751610066.

It can be written as a sum of positive squares in 6 ways, for example, as 6496843609 + 59504772096 = 80603^2 + 243936^2 .

It is not a de Polignac number, because 66001615705 - 2¹ = 66001615703 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66001615703) 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 11 ways as a sum of consecutive naturals, for example, 3917926 + ... + 3934735.

It is an arithmetic number, because the mean of its divisors is an integer number (6765068313).

Almost surely, 2^66001615705 is an apocalyptic number.

It is an amenable number.

66001615705 is a deficient number, since it is larger than the sum of its proper divisors (15179204051).

66001615705 is an equidigital number, since it uses as much as digits as its factorization.

66001615705 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7852748 (or 7852707 counting only the distinct ones).

The product of its (nonzero) digits is 37800, while the sum is 37.

The spelling of 66001615705 in words is "sixty-six billion, one million, six hundred fifteen thousand, seven hundred five".