166716643 has 2 divisors, whose sum is σ = 166716644. Its totient is φ = 166716642.

The previous prime is 166716631. The next prime is 166716749. The reversal of 166716643 is 346617661.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 166716643 - 2⁵ = 166716611 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 166716596 and 166716605.

It is not a weakly prime, because it can be changed into another prime (166716343) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83358321 + 83358322.

It is an arithmetic number, because the mean of its divisors is an integer number (83358322).

Almost surely, 2^166716643 is an apocalyptic number.

166716643 is a deficient number, since it is larger than the sum of its proper divisors (1).

166716643 is an equidigital number, since it uses as much as digits as its factorization.

166716643 is an evil number, because the sum of its binary digits is even.

The product of its digits is 108864, while the sum is 40.

The square root of 166716643 is about 12911.8799173474. The cubic root of 166716643 is about 550.3762087243.

The spelling of 166716643 in words is "one hundred sixty-six million, seven hundred sixteen thousand, six hundred forty-three".