665131027243 has 4 divisors (see below), whose sum is σ = 666137277568. Its totient is φ = 664124776920.

The previous prime is 665131027217. The next prime is 665131027247. The reversal of 665131027243 is 342720131566.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 342720131566 = 2 ⋅171360065783.

It is a cyclic number.

It is not a de Polignac number, because 665131027243 - 2³³ = 656541092651 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 665131027196 and 665131027205.

It is not an unprimeable number, because it can be changed into a prime (665131027247) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 503124171 + ... + 503125492.

It is an arithmetic number, because the mean of its divisors is an integer number (166534319392).

Almost surely, 2^665131027243 is an apocalyptic number.

665131027243 is a deficient number, since it is larger than the sum of its proper divisors (1006250325).

665131027243 is a wasteful number, since it uses less digits than its factorization.

665131027243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1006250324.

The product of its (nonzero) digits is 181440, while the sum is 40.

The spelling of 665131027243 in words is "six hundred sixty-five billion, one hundred thirty-one million, twenty-seven thousand, two hundred forty-three".