166087843636993 has 2 divisors, whose sum is σ = 166087843636994. Its totient is φ = 166087843636992.

The previous prime is 166087843636937. The next prime is 166087843637021. The reversal of 166087843636993 is 399636348780661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 137419186643649 + 28668656993344 = 11722593^2 + 5354312^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-166087843636993 is a prime.

It is not a weakly prime, because it can be changed into another prime (166087843630993) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83043921818496 + 83043921818497.

It is an arithmetic number, because the mean of its divisors is an integer number (83043921818497).

Almost surely, 2^{166087843636993} is an apocalyptic number.

It is an amenable number.

166087843636993 is a deficient number, since it is larger than the sum of its proper divisors (1).

166087843636993 is an equidigital number, since it uses as much as digits as its factorization.

166087843636993 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5079158784, while the sum is 79.

The spelling of 166087843636993 in words is "one hundred sixty-six trillion, eighty-seven billion, eight hundred forty-three million, six hundred thirty-six thousand, nine hundred ninety-three".