491649185329 has 3 divisors (see below), whose sum is σ = 491649886507. Its totient is φ = 491648484152.

The previous prime is 491649185281. The next prime is 491649185383. The reversal of 491649185329 is 923581946194.

The square root of 491649185329 is 701177.

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, and also an emirpimes, since its reverse is a distinct semiprime: 923581946194 = 2 ⋅461790973097.

It can be written as a sum of positive squares in only one way, i.e., 431353400625 + 60295784704 = 656775^2 + 245552^2 .

It is not a de Polignac number, because 491649185329 - 2²³ = 491640796721 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (491649185399) 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 2 ways as a sum of consecutive naturals, for example, 350589 + ... + 1051765.

Almost surely, 2^491649185329 is an apocalyptic number.

491649185329 is the 701177-th square number.

491649185329 is the 350589-th centered octagonal number.

It is an amenable number.

491649185329 is a deficient number, since it is larger than the sum of its proper divisors (701178).

491649185329 is an frugal number, since it uses more digits than its factorization.

491649185329 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1402354 (or 701177 counting only the distinct ones).

The product of its digits is 16796160, while the sum is 61.

The spelling of 491649185329 in words is "four hundred ninety-one billion, six hundred forty-nine million, one hundred eighty-five thousand, three hundred twenty-nine".