207893138209 has 3 divisors (see below), whose sum is σ = 207893594163. Its totient is φ = 207892682256.

The previous prime is 207893138191. The next prime is 207893138237. The reversal of 207893138209 is 902831398702.

The square root of 207893138209 is 455953.

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

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in only one way, i.e., 179085544225 + 28807593984 = 423185^2 + 169728^2 .

It is not a de Polignac number, because 207893138209 - 2¹³ = 207893130017 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (207893138239) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 227977 + ... + 683929.

It is an arithmetic number, because the mean of its divisors is an integer number (69297864721).

Almost surely, 2^207893138209 is an apocalyptic number.

207893138209 is the 455953-rd square number.

207893138209 is the 227977-th centered octagonal number.

It is an amenable number.

207893138209 is a deficient number, since it is larger than the sum of its proper divisors (455954).

207893138209 is an frugal number, since it uses more digits than its factorization.

207893138209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 911906 (or 455953 counting only the distinct ones).

The product of its (nonzero) digits is 1306368, while the sum is 52.

The spelling of 207893138209 in words is "two hundred seven billion, eight hundred ninety-three million, one hundred thirty-eight thousand, two hundred nine".