206885793409 has 3 divisors (see below), whose sum is σ = 206886248257. Its totient is φ = 206885338562.

The previous prime is 206885793383. The next prime is 206885793419. The reversal of 206885793409 is 904397588602.

The square root of 206885793409 is 454847.

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 is a de Polignac number, because none of the positive numbers 2^k-206885793409 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (206885793419) 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, 227424 + ... + 682270.

Almost surely, 2^206885793409 is an apocalyptic number.

206885793409 is the 454847-th square number.

206885793409 is the 227424-th centered octagonal number.

It is an amenable number.

206885793409 is a deficient number, since it is larger than the sum of its proper divisors (454848).

206885793409 is an frugal number, since it uses more digits than its factorization.

206885793409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 909694 (or 454847 counting only the distinct ones).

The product of its (nonzero) digits is 26127360, while the sum is 61.

The spelling of 206885793409 in words is "two hundred six billion, eight hundred eighty-five million, seven hundred ninety-three thousand, four hundred nine".