665223504145 has 16 divisors (see below), whose sum is σ = 806915059920. Its totient is φ = 526432743424.

The previous prime is 665223504097. The next prime is 665223504149. The reversal of 665223504145 is 541405322566.

It can be written as a sum of positive squares in 8 ways, for example, as 8736267024 + 656487237121 = 93468^2 + 810239^2 .

It is a cyclic number.

It is not a de Polignac number, because 665223504145 - 2³⁷ = 527784550673 is a prime.

It is not an unprimeable number, because it can be changed into a prime (665223504149) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 868984 + ... + 1444153.

It is an arithmetic number, because the mean of its divisors is an integer number (50432191245).

Almost surely, 2^665223504145 is an apocalyptic number.

It is an amenable number.

665223504145 is a deficient number, since it is larger than the sum of its proper divisors (141691555775).

665223504145 is a wasteful number, since it uses less digits than its factorization.

665223504145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2313764.

The product of its (nonzero) digits is 864000, while the sum is 43.

The spelling of 665223504145 in words is "six hundred sixty-five billion, two hundred twenty-three million, five hundred four thousand, one hundred forty-five".