665576785 has 8 divisors (see below), whose sum is σ = 798976296. Its totient is φ = 532272000.

The previous prime is 665576777. The next prime is 665576803. The reversal of 665576785 is 587675566.

It can be written as a sum of positive squares in 4 ways, for example, as 218211984 + 447364801 = 14772^2 + 21151^2 .

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

It is not a de Polignac number, because 665576785 - 2³ = 665576777 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7174 + ... + 37183.

It is an arithmetic number, because the mean of its divisors is an integer number (99872037).

Almost surely, 2^665576785 is an apocalyptic number.

It is an amenable number.

665576785 is a deficient number, since it is larger than the sum of its proper divisors (133399511).

665576785 is a wasteful number, since it uses less digits than its factorization.

665576785 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47363.

The product of its digits is 10584000, while the sum is 55.

The square root of 665576785 is about 25798.7748740129. The cubic root of 665576785 is about 873.1041554151.

The spelling of 665576785 in words is "six hundred sixty-five million, five hundred seventy-six thousand, seven hundred eighty-five".