161009 has 2 divisors, whose sum is σ = 161010. Its totient is φ = 161008.

The previous prime is 160997. The next prime is 161017. The reversal of 161009 is 900161.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 87025 + 73984 = 295^2 + 272^2 .

It is an emirp because it is prime and its reverse (900161) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 161009 - 2⁸ = 160753 is a prime.

It is a Chen prime.

It is a nialpdrome in base 11.

It is not a weakly prime, because it can be changed into another prime (161039) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80504 + 80505.

It is an arithmetic number, because the mean of its divisors is an integer number (80505).

2¹⁶¹⁰⁰⁹ is an apocalyptic number.

It is an amenable number.

161009 is a deficient number, since it is larger than the sum of its proper divisors (1).

161009 is an equidigital number, since it uses as much as digits as its factorization.

161009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 54, while the sum is 17.

The square root of 161009 is about 401.2592678057. The cubic root of 161009 is about 54.4022319226.

The spelling of 161009 in words is "one hundred sixty-one thousand, nine".