165278081 has 8 divisors (see below), whose sum is σ = 170859264. Its totient is φ = 159712560.

The previous prime is 165278051. The next prime is 165278129. The reversal of 165278081 is 180872561.

165278081 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 165278081 - 2¹⁸ = 165015937 is a prime.

It is a super-2 number, since 2×165278081² = 54633688118085122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (165278021) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19946 + ... + 26988.

It is an arithmetic number, because the mean of its divisors is an integer number (21357408).

Almost surely, 2^165278081 is an apocalyptic number.

It is an amenable number.

165278081 is a deficient number, since it is larger than the sum of its proper divisors (5581183).

165278081 is an equidigital number, since it uses as much as digits as its factorization.

165278081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7831.

The product of its (nonzero) digits is 26880, while the sum is 38.

The square root of 165278081 is about 12856.0523100989. The cubic root of 165278081 is about 548.7886076583.

The spelling of 165278081 in words is "one hundred sixty-five million, two hundred seventy-eight thousand, eighty-one".