165901 has 2 divisors, whose sum is σ = 165902. Its totient is φ = 165900.

The previous prime is 165887. The next prime is 165931. The reversal of 165901 is 109561.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 121801 + 44100 = 349^2 + 210^2 .

It is a cyclic number.

It is not a de Polignac number, because 165901 - 2¹¹ = 163853 is a prime.

It is an Ulam number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (165931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82950 + 82951.

It is an arithmetic number, because the mean of its divisors is an integer number (82951).

2¹⁶⁵⁹⁰¹ is an apocalyptic number.

It is an amenable number.

165901 is a deficient number, since it is larger than the sum of its proper divisors (1).

165901 is an equidigital number, since it uses as much as digits as its factorization.

165901 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 270, while the sum is 22.

The square root of 165901 is about 407.3094646580. The cubic root of 165901 is about 54.9477189142.

The spelling of 165901 in words is "one hundred sixty-five thousand, nine hundred one".