166387643 has 2 divisors, whose sum is σ = 166387644. Its totient is φ = 166387642.

The previous prime is 166387607. The next prime is 166387651. The reversal of 166387643 is 346783661.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 166387643 - 2²⁰ = 165339067 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 166387594 and 166387603.

It is not a weakly prime, because it can be changed into another prime (166387603) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83193821 + 83193822.

It is an arithmetic number, because the mean of its divisors is an integer number (83193822).

Almost surely, 2^166387643 is an apocalyptic number.

166387643 is a deficient number, since it is larger than the sum of its proper divisors (1).

166387643 is an equidigital number, since it uses as much as digits as its factorization.

166387643 is an evil number, because the sum of its binary digits is even.

The product of its digits is 435456, while the sum is 44.

The square root of 166387643 is about 12899.1334205054. The cubic root of 166387643 is about 550.0139313276.

The spelling of 166387643 in words is "one hundred sixty-six million, three hundred eighty-seven thousand, six hundred forty-three".