491161645 has 8 divisors (see below), whose sum is σ = 634732056. Its totient is φ = 362703936.

The previous prime is 491161633. The next prime is 491161667. The reversal of 491161645 is 546161194.

It can be written as a sum of positive squares in 4 ways, for example, as 55980324 + 435181321 = 7482^2 + 20861^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 491161645 - 2²¹ = 489064493 is a prime.

It is a super-3 number, since 3×491161645³ (a number of 27 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 3778102 + ... + 3778231.

It is an arithmetic number, because the mean of its divisors is an integer number (79341507).

Almost surely, 2^491161645 is an apocalyptic number.

It is an amenable number.

491161645 is a deficient number, since it is larger than the sum of its proper divisors (143570411).

491161645 is a wasteful number, since it uses less digits than its factorization.

491161645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7556351.

The product of its digits is 25920, while the sum is 37.

The square root of 491161645 is about 22162.1669743732. The cubic root of 491161645 is about 788.9960247459.

The spelling of 491161645 in words is "four hundred ninety-one million, one hundred sixty-one thousand, six hundred forty-five".