168165449 has 4 divisors (see below), whose sum is σ = 171338436. Its totient is φ = 164992464.

The previous prime is 168165401. The next prime is 168165451. The reversal of 168165449 is 944561861.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 944561861 = 23 ⋅41067907.

It can be written as a sum of positive squares in 2 ways, for example, as 137639824 + 30525625 = 11732^2 + 5525^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-168165449 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (168165469) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1586414 + ... + 1586519.

It is an arithmetic number, because the mean of its divisors is an integer number (42834609).

Almost surely, 2^168165449 is an apocalyptic number.

It is an amenable number.

168165449 is a deficient number, since it is larger than the sum of its proper divisors (3172987).

168165449 is an equidigital number, since it uses as much as digits as its factorization.

168165449 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3172986.

The product of its digits is 207360, while the sum is 44.

The square root of 168165449 is about 12967.8621599707. The cubic root of 168165449 is about 551.9659112622.

The spelling of 168165449 in words is "one hundred sixty-eight million, one hundred sixty-five thousand, four hundred forty-nine".