169988816209 has 9 divisors (see below), whose sum is σ = 172446442441. Its totient is φ = 167565746740.

The previous prime is 169988816197. The next prime is 169988816213. The reversal of 169988816209 is 902618889961.

The square root of 169988816209 is 412297.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 169988816209 - 2⁵ = 169988816177 is a prime.

It is a super-2 number, since 2×169988816209² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (169988816279) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 29270184 + ... + 29275990.

Almost surely, 2^169988816209 is an apocalyptic number.

169988816209 is the 412297-th square number.

169988816209 is the 206149-th centered octagonal number.

It is an amenable number.

169988816209 is a deficient number, since it is larger than the sum of its proper divisors (2457626232).

169988816209 is an frugal number, since it uses more digits than its factorization.

169988816209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11756 (or 5878 counting only the distinct ones).

The product of its (nonzero) digits is 26873856, while the sum is 67.

The spelling of 169988816209 in words is "one hundred sixty-nine billion, nine hundred eighty-eight million, eight hundred sixteen thousand, two hundred nine".