491531603 has 4 divisors (see below), whose sum is σ = 497054520. Its totient is φ = 486008688.

The previous prime is 491531587. The next prime is 491531609. The reversal of 491531603 is 306135194.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 491531603 - 2⁴ = 491531587 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 491531603.

It is not an unprimeable number, because it can be changed into a prime (491531609) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2761325 + ... + 2761502.

It is an arithmetic number, because the mean of its divisors is an integer number (124263630).

Almost surely, 2^491531603 is an apocalyptic number.

491531603 is a deficient number, since it is larger than the sum of its proper divisors (5522917).

491531603 is an equidigital number, since it uses as much as digits as its factorization.

491531603 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5522916.

The product of its (nonzero) digits is 9720, while the sum is 32.

The square root of 491531603 is about 22170.5120148363. The cubic root of 491531603 is about 789.1940736889.

Adding to 491531603 its reverse (306135194), we get a palindrome (797666797).

The spelling of 491531603 in words is "four hundred ninety-one million, five hundred thirty-one thousand, six hundred three".