165278741 has 4 divisors (see below), whose sum is σ = 169745772. Its totient is φ = 160811712.

The previous prime is 165278717. The next prime is 165278753. The reversal of 165278741 is 147872561.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 147872561 = 109 ⋅1356629.

It can be written as a sum of positive squares in 2 ways, for example, as 74476900 + 90801841 = 8630^2 + 9529^2 .

It is a cyclic number.

It is not a de Polignac number, because 165278741 - 2⁶ = 165278677 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165278761) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2233460 + ... + 2233533.

It is an arithmetic number, because the mean of its divisors is an integer number (42436443).

Almost surely, 2^165278741 is an apocalyptic number.

It is an amenable number.

165278741 is a deficient number, since it is larger than the sum of its proper divisors (4467031).

165278741 is an equidigital number, since it uses as much as digits as its factorization.

165278741 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4467030.

The product of its digits is 94080, while the sum is 41.

The square root of 165278741 is about 12856.0779789172. The cubic root of 165278741 is about 548.7893381443.

The spelling of 165278741 in words is "one hundred sixty-five million, two hundred seventy-eight thousand, seven hundred forty-one".