165666433 has 2 divisors, whose sum is σ = 165666434. Its totient is φ = 165666432.

The previous prime is 165666421. The next prime is 165666437. The reversal of 165666433 is 334666561.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 127622209 + 38044224 = 11297^2 + 6168^2 .

It is an emirp because it is prime and its reverse (334666561) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-165666433 is a prime.

It is not a weakly prime, because it can be changed into another prime (165666437) 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, 82833216 + 82833217.

It is an arithmetic number, because the mean of its divisors is an integer number (82833217).

Almost surely, 2^165666433 is an apocalyptic number.

It is an amenable number.

165666433 is a deficient number, since it is larger than the sum of its proper divisors (1).

165666433 is an equidigital number, since it uses as much as digits as its factorization.

165666433 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 233280, while the sum is 40.

The square root of 165666433 is about 12871.1473070585. The cubic root of 165666433 is about 549.2180988634.

The spelling of 165666433 in words is "one hundred sixty-five million, six hundred sixty-six thousand, four hundred thirty-three".