665360516731 has 2 divisors, whose sum is σ = 665360516732. Its totient is φ = 665360516730.

The previous prime is 665360516701. The next prime is 665360516741. The reversal of 665360516731 is 137615063566.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 665360516731 - 2¹⁷ = 665360385659 is a prime.

It is a super-2 number, since 2×665360516731² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (665360516701) 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, 332680258365 + 332680258366.

It is an arithmetic number, because the mean of its divisors is an integer number (332680258366).

Almost surely, 2^665360516731 is an apocalyptic number.

665360516731 is a deficient number, since it is larger than the sum of its proper divisors (1).

665360516731 is an equidigital number, since it uses as much as digits as its factorization.

665360516731 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2041200, while the sum is 49.

The spelling of 665360516731 in words is "six hundred sixty-five billion, three hundred sixty million, five hundred sixteen thousand, seven hundred thirty-one".