491965 has 8 divisors (see below), whose sum is σ = 600408. Its totient is φ = 386880.

The previous prime is 491951. The next prime is 491969. The reversal of 491965 is 569194.

It can be written as a sum of positive squares in 4 ways, for example, as 3364 + 488601 = 58^2 + 699^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 491965 - 2⁷ = 491837 is a prime.

It is a super-2 number, since 2×491965² = 484059122450, which contains 22 as substring.

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 491965.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (491969) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 502 + ... + 1111.

It is an arithmetic number, because the mean of its divisors is an integer number (75051).

2⁴⁹¹⁹⁶⁵ is an apocalyptic number.

It is an amenable number.

491965 is a deficient number, since it is larger than the sum of its proper divisors (108443).

491965 is a wasteful number, since it uses less digits than its factorization.

491965 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1679.

The product of its digits is 9720, while the sum is 34.

The square root of 491965 is about 701.4021670910. The cubic root of 491965 is about 78.9425956959.

The spelling of 491965 in words is "four hundred ninety-one thousand, nine hundred sixty-five".