165644887 has 2 divisors, whose sum is σ = 165644888. Its totient is φ = 165644886.

The previous prime is 165644861. The next prime is 165644903. The reversal of 165644887 is 788446561.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-165644887 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 165644887.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (165644807) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82822443 + 82822444.

It is an arithmetic number, because the mean of its divisors is an integer number (82822444).

Almost surely, 2^165644887 is an apocalyptic number.

165644887 is a deficient number, since it is larger than the sum of its proper divisors (1).

165644887 is an equidigital number, since it uses as much as digits as its factorization.

165644887 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1290240, while the sum is 49.

The square root of 165644887 is about 12870.3102915198. The cubic root of 165644887 is about 549.1942880326.

The spelling of 165644887 in words is "one hundred sixty-five million, six hundred forty-four thousand, eight hundred eighty-seven".