165635161 has 2 divisors, whose sum is σ = 165635162. Its totient is φ = 165635160.

The previous prime is 165635159. The next prime is 165635177. The reversal of 165635161 is 161536561.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 96412761 + 69222400 = 9819^2 + 8320^2 .

It is a cyclic number.

It is not a de Polignac number, because 165635161 - 2¹ = 165635159 is a prime.

Together with 165635159, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (165635101) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82817580 + 82817581.

It is an arithmetic number, because the mean of its divisors is an integer number (82817581).

Almost surely, 2^165635161 is an apocalyptic number.

It is an amenable number.

165635161 is a deficient number, since it is larger than the sum of its proper divisors (1).

165635161 is an equidigital number, since it uses as much as digits as its factorization.

165635161 is an evil number, because the sum of its binary digits is even.

The product of its digits is 16200, while the sum is 34.

The square root of 165635161 is about 12869.9324396051. The cubic root of 165635161 is about 549.1835389974.

The spelling of 165635161 in words is "one hundred sixty-five million, six hundred thirty-five thousand, one hundred sixty-one".