665848193 has 8 divisors (see below), whose sum is σ = 669814440. Its totient is φ = 661893120.

The previous prime is 665848177. The next prime is 665848243. The reversal of 665848193 is 391848566.

It can be written as a sum of positive squares in 4 ways, for example, as 106667584 + 559180609 = 10328^2 + 23647^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 665848193 - 2⁴ = 665848177 is a prime.

It is a super-2 number, since 2×665848193² = 886707632242730498, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (665818193) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 136643 + ... + 141431.

It is an arithmetic number, because the mean of its divisors is an integer number (83726805).

Almost surely, 2^665848193 is an apocalyptic number.

It is an amenable number.

665848193 is a deficient number, since it is larger than the sum of its proper divisors (3966247).

665848193 is a wasteful number, since it uses less digits than its factorization.

665848193 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5587.

The product of its digits is 1244160, while the sum is 50.

The square root of 665848193 is about 25804.0344326231. The cubic root of 665848193 is about 873.2228170307. Note that the first 3 decimals are identical.

The spelling of 665848193 in words is "six hundred sixty-five million, eight hundred forty-eight thousand, one hundred ninety-three".