65166768091 has 2 divisors, whose sum is σ = 65166768092. Its totient is φ = 65166768090.

The previous prime is 65166768071. The next prime is 65166768143. The reversal of 65166768091 is 19086766156.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 65166768091 - 2⁹ = 65166767579 is a prime.

It is not a weakly prime, because it can be changed into another prime (65166768031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32583384045 + 32583384046.

It is an arithmetic number, because the mean of its divisors is an integer number (32583384046).

Almost surely, 2^65166768091 is an apocalyptic number.

65166768091 is a deficient number, since it is larger than the sum of its proper divisors (1).

65166768091 is an equidigital number, since it uses as much as digits as its factorization.

65166768091 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3265920, while the sum is 55.

The spelling of 65166768091 in words is "sixty-five billion, one hundred sixty-six million, seven hundred sixty-eight thousand, ninety-one".