666665064845623 has 2 divisors, whose sum is σ = 666665064845624. Its totient is φ = 666665064845622.

The previous prime is 666665064845501. The next prime is 666665064845669. The reversal of 666665064845623 is 326548460566666.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-666665064845623 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (666665064846623) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333332532422811 + 333332532422812.

It is an arithmetic number, because the mean of its divisors is an integer number (333332532422812).

Almost surely, 2^{666665064845623} is an apocalyptic number.

666665064845623 is a deficient number, since it is larger than the sum of its proper divisors (1).

666665064845623 is an equidigital number, since it uses as much as digits as its factorization.

666665064845623 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5374771200, while the sum is 73.

The spelling of 666665064845623 in words is "six hundred sixty-six trillion, six hundred sixty-five billion, sixty-four million, eight hundred forty-five thousand, six hundred twenty-three".