166440044647 has 2 divisors, whose sum is σ = 166440044648. Its totient is φ = 166440044646.

The previous prime is 166440044623. The next prime is 166440044689. The reversal of 166440044647 is 746440044661.

It is a weak prime.

It is an emirp because it is prime and its reverse (746440044661) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 166440044647 - 2²⁷ = 166305826919 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 166440044597 and 166440044606.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (166440044047) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83220022323 + 83220022324.

It is an arithmetic number, because the mean of its divisors is an integer number (83220022324).

Almost surely, 2^166440044647 is an apocalyptic number.

166440044647 is a deficient number, since it is larger than the sum of its proper divisors (1).

166440044647 is an equidigital number, since it uses as much as digits as its factorization.

166440044647 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1548288, while the sum is 46.

The spelling of 166440044647 in words is "one hundred sixty-six billion, four hundred forty million, forty-four thousand, six hundred forty-seven".