665249360851 has 2 divisors, whose sum is σ = 665249360852. Its totient is φ = 665249360850.

The previous prime is 665249360803. The next prime is 665249360861. The reversal of 665249360851 is 158063942566.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 665249360851 - 2¹⁷ = 665249229779 is a prime.

It is a super-2 number, since 2×665249360851² (a number of 24 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 665249360792 and 665249360801.

It is not a weakly prime, because it can be changed into another prime (665249360861) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332624680425 + 332624680426.

It is an arithmetic number, because the mean of its divisors is an integer number (332624680426).

Almost surely, 2^665249360851 is an apocalyptic number.

665249360851 is a deficient number, since it is larger than the sum of its proper divisors (1).

665249360851 is an equidigital number, since it uses as much as digits as its factorization.

665249360851 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9331200, while the sum is 55.

The spelling of 665249360851 in words is "six hundred sixty-five billion, two hundred forty-nine million, three hundred sixty thousand, eight hundred fifty-one".