491739587 has 2 divisors, whose sum is σ = 491739588. Its totient is φ = 491739586.

The previous prime is 491739581. The next prime is 491739601. The reversal of 491739587 is 785937194.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-491739587 is a prime.

It is not a weakly prime, because it can be changed into another prime (491739581) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 245869793 + 245869794.

It is an arithmetic number, because the mean of its divisors is an integer number (245869794).

Almost surely, 2^491739587 is an apocalyptic number.

491739587 is a deficient number, since it is larger than the sum of its proper divisors (1).

491739587 is an equidigital number, since it uses as much as digits as its factorization.

491739587 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1905120, while the sum is 53.

The square root of 491739587 is about 22175.2020734874. The cubic root of 491739587 is about 789.3053697504.

The spelling of 491739587 in words is "four hundred ninety-one million, seven hundred thirty-nine thousand, five hundred eighty-seven".