491587 has 4 divisors (see below), whose sum is σ = 517480. Its totient is φ = 465696.

The previous prime is 491581. The next prime is 491591. The reversal of 491587 is 785194.

It is a happy number.

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 491587 - 2¹¹ = 489539 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (491581) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12918 + ... + 12955.

It is an arithmetic number, because the mean of its divisors is an integer number (129370).

2⁴⁹¹⁵⁸⁷ is an apocalyptic number.

491587 is a deficient number, since it is larger than the sum of its proper divisors (25893).

491587 is a wasteful number, since it uses less digits than its factorization.

491587 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25892.

The product of its digits is 10080, while the sum is 34.

The square root of 491587 is about 701.1326550661. The cubic root of 491587 is about 78.9223720709.

The spelling of 491587 in words is "four hundred ninety-one thousand, five hundred eighty-seven".