169897729 has 4 divisors (see below), whose sum is σ = 172433584. Its totient is φ = 167361876.

The previous prime is 169897681. The next prime is 169897771. The reversal of 169897729 is 927798961.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 927798961 = 71 ⋅13067591.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-169897729 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (169897789) 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, 1267827 + ... + 1267960.

It is an arithmetic number, because the mean of its divisors is an integer number (43108396).

Almost surely, 2^169897729 is an apocalyptic number.

It is an amenable number.

169897729 is a deficient number, since it is larger than the sum of its proper divisors (2535855).

169897729 is an equidigital number, since it uses as much as digits as its factorization.

169897729 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2535854.

The product of its digits is 3429216, while the sum is 58.

The square root of 169897729 is about 13034.4823065590. The cubic root of 169897729 is about 553.8547158641.

The spelling of 169897729 in words is "one hundred sixty-nine million, eight hundred ninety-seven thousand, seven hundred twenty-nine".