665660086 has 64 divisors (see below), whose sum is σ = 1279918080. Its totient is φ = 252564480.

The previous prime is 665660077. The next prime is 665660087. The reversal of 665660086 is 680066566.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665660087) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 716070 + ... + 716998.

It is an arithmetic number, because the mean of its divisors is an integer number (19998720).

Almost surely, 2^665660086 is an apocalyptic number.

665660086 is a deficient number, since it is larger than the sum of its proper divisors (614257994).

665660086 is a wasteful number, since it uses less digits than its factorization.

665660086 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1109.

The product of its (nonzero) digits is 311040, while the sum is 43.

The square root of 665660086 is about 25800.3892606294. The cubic root of 665660086 is about 873.1405786683.

The spelling of 665660086 in words is "six hundred sixty-five million, six hundred sixty thousand, eighty-six".