165139285 has 4 divisors (see below), whose sum is σ = 198167148. Its totient is φ = 132111424.

The previous prime is 165139277. The next prime is 165139297. The reversal of 165139285 is 582931561.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 582931561 = 2551 ⋅228511.

It can be written as a sum of positive squares in 2 ways, for example, as 65658609 + 99480676 = 8103^2 + 9974^2 .

It is a cyclic number.

It is not a de Polignac number, because 165139285 - 2³ = 165139277 is a prime.

It is a super-2 number, since 2×165139285² = 54541966900622450, which contains 22 as substring.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 16513924 + ... + 16513933.

It is an arithmetic number, because the mean of its divisors is an integer number (49541787).

Almost surely, 2^165139285 is an apocalyptic number.

It is an amenable number.

165139285 is a deficient number, since it is larger than the sum of its proper divisors (33027863).

165139285 is an equidigital number, since it uses as much as digits as its factorization.

165139285 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33027862.

The product of its digits is 64800, while the sum is 40.

The square root of 165139285 is about 12850.6530962438. The cubic root of 165139285 is about 548.6349454287.

The spelling of 165139285 in words is "one hundred sixty-five million, one hundred thirty-nine thousand, two hundred eighty-five".