66465785 has 4 divisors (see below), whose sum is σ = 79758948. Its totient is φ = 53172624.

The previous prime is 66465779. The next prime is 66465811. The reversal of 66465785 is 58756466.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 58756466 = 2 ⋅29378233.

It can be written as a sum of positive squares in 2 ways, for example, as 10679824 + 55785961 = 3268^2 + 7469^2 .

It is a cyclic number.

It is not a de Polignac number, because 66465785 - 2¹⁴ = 66449401 is a prime.

It is a Duffinian number.

It is a Curzon number.

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 3 ways as a sum of consecutive naturals, for example, 6646574 + ... + 6646583.

It is an arithmetic number, because the mean of its divisors is an integer number (19939737).

Almost surely, 2^66465785 is an apocalyptic number.

It is an amenable number.

66465785 is a deficient number, since it is larger than the sum of its proper divisors (13293163).

66465785 is a wasteful number, since it uses less digits than its factorization.

66465785 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13293162.

The product of its digits is 1209600, while the sum is 47.

The square root of 66465785 is about 8152.6550889879. The cubic root of 66465785 is about 405.0724556645.

The spelling of 66465785 in words is "sixty-six million, four hundred sixty-five thousand, seven hundred eighty-five".