165290705 has 4 divisors (see below), whose sum is σ = 198348852. Its totient is φ = 132232560.

The previous prime is 165290701. The next prime is 165290707. The reversal of 165290705 is 507092561.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 507092561 = 11279 ⋅44959.

It can be written as a sum of positive squares in 2 ways, for example, as 51825601 + 113465104 = 7199^2 + 10652^2 .

It is not a de Polignac number, because 165290705 - 2² = 165290701 is a prime.

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

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (165290701) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16529066 + ... + 16529075.

It is an arithmetic number, because the mean of its divisors is an integer number (49587213).

Almost surely, 2^165290705 is an apocalyptic number.

It is an amenable number.

165290705 is a deficient number, since it is larger than the sum of its proper divisors (33058147).

165290705 is an equidigital number, since it uses as much as digits as its factorization.

165290705 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33058146.

The product of its (nonzero) digits is 18900, while the sum is 35.

The square root of 165290705 is about 12856.5432757021. The cubic root of 165290705 is about 548.8025795271.

The spelling of 165290705 in words is "one hundred sixty-five million, two hundred ninety thousand, seven hundred five".