491801 has 4 divisors (see below), whose sum is σ = 498612. Its totient is φ = 484992.

The previous prime is 491797. The next prime is 491819. The reversal of 491801 is 108194.

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

It can be written as a sum of positive squares in 2 ways, for example, as 265225 + 226576 = 515^2 + 476^2 .

It is a cyclic number.

It is not a de Polignac number, because 491801 - 2² = 491797 is a prime.

It is a Duffinian number.

It is a plaindrome in base 15.

It is not an unprimeable number, because it can be changed into a prime (491851) 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, 3296 + ... + 3441.

It is an arithmetic number, because the mean of its divisors is an integer number (124653).

2⁴⁹¹⁸⁰¹ is an apocalyptic number.

It is an amenable number.

491801 is a deficient number, since it is larger than the sum of its proper divisors (6811).

491801 is an equidigital number, since it uses as much as digits as its factorization.

491801 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6810.

The product of its (nonzero) digits is 288, while the sum is 23.

The square root of 491801 is about 701.2852486685. The cubic root of 491801 is about 78.9338226974.

Adding to 491801 its reverse (108194), we get a palindrome (599995).

The spelling of 491801 in words is "four hundred ninety-one thousand, eight hundred one".