665155055523 has 16 divisors (see below), whose sum is σ = 1066915377920. Its totient is φ = 360083939616.

The previous prime is 665155055479. The next prime is 665155055527. The reversal of 665155055523 is 325550551566.

It is a happy number.

It is not a de Polignac number, because 665155055523 - 2⁶ = 665155055459 is a prime.

It is not an unprimeable number, because it can be changed into a prime (665155055527) 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 in 15 ways as a sum of consecutive naturals, for example, 833527240 + ... + 833528037.

It is an arithmetic number, because the mean of its divisors is an integer number (66682211120).

Almost surely, 2^665155055523 is an apocalyptic number.

665155055523 is a deficient number, since it is larger than the sum of its proper divisors (401760322397).

665155055523 is a wasteful number, since it uses less digits than its factorization.

665155055523 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1667055306.

The product of its (nonzero) digits is 3375000, while the sum is 48.

The spelling of 665155055523 in words is "six hundred sixty-five billion, one hundred fifty-five million, fifty-five thousand, five hundred twenty-three".