165505243 has 8 divisors (see below), whose sum is σ = 166425408. Its totient is φ = 164588424.

The previous prime is 165505231. The next prime is 165505247. The reversal of 165505243 is 342505561.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 165505243 - 2²⁵ = 131950811 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (165505247) 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 in 7 ways as a sum of consecutive naturals, for example, 241980 + ... + 242662.

It is an arithmetic number, because the mean of its divisors is an integer number (20803176).

Almost surely, 2^165505243 is an apocalyptic number.

165505243 is a deficient number, since it is larger than the sum of its proper divisors (920165).

165505243 is an equidigital number, since it uses as much as digits as its factorization.

165505243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1673.

The product of its (nonzero) digits is 18000, while the sum is 31.

The square root of 165505243 is about 12864.8841036365. The cubic root of 165505243 is about 549.0399151252.

The spelling of 165505243 in words is "one hundred sixty-five million, five hundred five thousand, two hundred forty-three".