491033009 has 4 divisors (see below), whose sum is σ = 491286900. Its totient is φ = 490779120.

The previous prime is 491032999. The next prime is 491033027. The reversal of 491033009 is 900330194.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 900330194 = 2 ⋅450165097.

It can be written as a sum of positive squares in 2 ways, for example, as 364695409 + 126337600 = 19097^2 + 11240^2 .

It is a cyclic number.

It is not a de Polignac number, because 491033009 - 2⁸ = 491032753 is a prime.

It is a super-2 number, since 2×491033009² = 482226831855188162, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (491033909) 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 3 ways as a sum of consecutive naturals, for example, 124022 + ... + 127919.

It is an arithmetic number, because the mean of its divisors is an integer number (122821725).

Almost surely, 2^491033009 is an apocalyptic number.

It is an amenable number.

491033009 is a deficient number, since it is larger than the sum of its proper divisors (253891).

491033009 is a wasteful number, since it uses less digits than its factorization.

491033009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 253890.

The product of its (nonzero) digits is 2916, while the sum is 29.

The square root of 491033009 is about 22159.2646313004. The cubic root of 491033009 is about 788.9271389691.

The spelling of 491033009 in words is "four hundred ninety-one million, thirty-three thousand, nine".