172808984209 has 9 divisors (see below), whose sum is σ = 174024206139. Its totient is φ = 171602198400.

The previous prime is 172808984077. The next prime is 172808984213. The reversal of 172808984209 is 902489808271.

The square root of 172808984209 is 415703.

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

172808984209 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 160724819025 + 12084165184 = 400905^2 + 109928^2 .

It is not a de Polignac number, because 172808984209 - 2¹³ = 172808976017 is a prime.

It is a super-2 number, since 2×172808984209² (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 (172808984009) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 62769777 + ... + 62772529.

Almost surely, 2^172808984209 is an apocalyptic number.

172808984209 is the 415703-rd square number.

172808984209 is the 207852-nd centered octagonal number.

It is an amenable number.

172808984209 is a deficient number, since it is larger than the sum of its proper divisors (1215221930).

172808984209 is an frugal number, since it uses more digits than its factorization.

172808984209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5808 (or 2904 counting only the distinct ones).

The product of its (nonzero) digits is 4644864, while the sum is 58.

The spelling of 172808984209 in words is "one hundred seventy-two billion, eight hundred eight million, nine hundred eighty-four thousand, two hundred nine".