169009409 has 4 divisors (see below), whose sum is σ = 169986516. Its totient is φ = 168032304.

The previous prime is 169009403. The next prime is 169009411. The reversal of 169009409 is 904900961.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 904900961 = 733 ⋅1234517.

It can be written as a sum of positive squares in 2 ways, for example, as 154455184 + 14554225 = 12428^2 + 3815^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-169009409 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (169009403) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 488294 + ... + 488639.

It is an arithmetic number, because the mean of its divisors is an integer number (42496629).

Almost surely, 2^169009409 is an apocalyptic number.

It is an amenable number.

169009409 is a deficient number, since it is larger than the sum of its proper divisors (977107).

169009409 is an equidigital number, since it uses as much as digits as its factorization.

169009409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 977106.

The product of its (nonzero) digits is 17496, while the sum is 38.

The square root of 169009409 is about 13000.3618795786. The cubic root of 169009409 is about 552.8877415803.

It can be divided in two parts, 16900 and 9409, that multiplied together give a square (159012100 = 12610²).

The spelling of 169009409 in words is "one hundred sixty-nine million, nine thousand, four hundred nine".