209162619649 has 9 divisors (see below), whose sum is σ = 216142102659. Its totient is φ = 202401718080.

The previous prime is 209162619607. The next prime is 209162619671. The reversal of 209162619649 is 946916261902.

The square root of 209162619649 is 457343.

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

It can be written as a sum of positive squares in only one way, i.e., 102646548225 + 106516071424 = 320385^2 + 326368^2 .

It is a de Polignac number, because none of the positive numbers 2^k-209162619649 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 209162619649.

It is not an unprimeable number, because it can be changed into a prime (209162619349) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 14170257 + ... + 14185009.

Almost surely, 2^209162619649 is an apocalyptic number.

209162619649 is the 457343-rd square number.

209162619649 is the 228672-nd centered octagonal number.

It is an amenable number.

209162619649 is a deficient number, since it is larger than the sum of its proper divisors (6979483010).

209162619649 is an frugal number, since it uses more digits than its factorization.

209162619649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29568 (or 14784 counting only the distinct ones).

The product of its (nonzero) digits is 2519424, while the sum is 55.

The spelling of 209162619649 in words is "two hundred nine billion, one hundred sixty-two million, six hundred nineteen thousand, six hundred forty-nine".