172680309 has 8 divisors (see below), whose sum is σ = 255822720. Its totient is φ = 115120188.

The previous prime is 172680293. The next prime is 172680331. The reversal of 172680309 is 903086271.

172680309 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 172680309 - 2⁴ = 172680293 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (172680349) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3197757 + ... + 3197810.

It is an arithmetic number, because the mean of its divisors is an integer number (31977840).

Almost surely, 2^172680309 is an apocalyptic number.

It is an amenable number.

172680309 is a deficient number, since it is larger than the sum of its proper divisors (83142411).

172680309 is an equidigital number, since it uses as much as digits as its factorization.

172680309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6395576 (or 6395570 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 36.

The square root of 172680309 is about 13140.7879900712. The cubic root of 172680309 is about 556.8620293094.

The spelling of 172680309 in words is "one hundred seventy-two million, six hundred eighty thousand, three hundred nine".