665514285509 has 2 divisors, whose sum is σ = 665514285510. Its totient is φ = 665514285508.

The previous prime is 665514285503. The next prime is 665514285547. The reversal of 665514285509 is 905582415566.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 637367512609 + 28146772900 = 798353^2 + 167770^2 .

It is a cyclic number.

It is not a de Polignac number, because 665514285509 - 2³² = 661219318213 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (665514285503) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332757142754 + 332757142755.

It is an arithmetic number, because the mean of its divisors is an integer number (332757142755).

Almost surely, 2^665514285509 is an apocalyptic number.

It is an amenable number.

665514285509 is a deficient number, since it is larger than the sum of its proper divisors (1).

665514285509 is an equidigital number, since it uses as much as digits as its factorization.

665514285509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12960000, while the sum is 56.

The spelling of 665514285509 in words is "six hundred sixty-five billion, five hundred fourteen million, two hundred eighty-five thousand, five hundred nine".