66438277585 has 16 divisors (see below), whose sum is σ = 80277986880. Its totient is φ = 52783099200.

The previous prime is 66438277553. The next prime is 66438277627. The reversal of 66438277585 is 58577283466.

It is not a de Polignac number, because 66438277585 - 2⁵ = 66438277553 is a prime.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 1028986 + ... + 1091644.

It is an arithmetic number, because the mean of its divisors is an integer number (5017374180).

Almost surely, 2^66438277585 is an apocalyptic number.

It is an amenable number.

66438277585 is a deficient number, since it is larger than the sum of its proper divisors (13839709295).

66438277585 is a wasteful number, since it uses less digits than its factorization.

66438277585 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64128.

The product of its digits is 67737600, while the sum is 61.

The spelling of 66438277585 in words is "sixty-six billion, four hundred thirty-eight million, two hundred seventy-seven thousand, five hundred eighty-five".