172909829 has 4 divisors (see below), whose sum is σ = 173175276. Its totient is φ = 172644384.

The previous prime is 172909813. The next prime is 172909853. The reversal of 172909829 is 928909271.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 928909271 = 433 ⋅2145287.

It can be written as a sum of positive squares in 2 ways, for example, as 100200100 + 72709729 = 10010^2 + 8527^2 .

It is a cyclic number.

It is not a de Polignac number, because 172909829 - 2⁴ = 172909813 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (172909859) 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, 131744 + ... + 133049.

It is an arithmetic number, because the mean of its divisors is an integer number (43293819).

Almost surely, 2^172909829 is an apocalyptic number.

It is an amenable number.

172909829 is a deficient number, since it is larger than the sum of its proper divisors (265447).

172909829 is an equidigital number, since it uses as much as digits as its factorization.

172909829 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 265446.

The product of its (nonzero) digits is 163296, while the sum is 47.

The square root of 172909829 is about 13149.5182041016. The cubic root of 172909829 is about 557.1086399167.

The spelling of 172909829 in words is "one hundred seventy-two million, nine hundred nine thousand, eight hundred twenty-nine".