491864 has 8 divisors (see below), whose sum is σ = 922260. Its totient is φ = 245928.

The previous prime is 491857. The next prime is 491867. The reversal of 491864 is 468194.

It is a tau number, because it is divible by the number of its divisors (8).

It is a self number, because there is not a number n which added to its sum of digits gives 491864.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (491867) by changing a digit.

491864 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30734 + ... + 30749.

2⁴⁹¹⁸⁶⁴ is an apocalyptic number.

It is an amenable number.

491864 is a deficient number, since it is larger than the sum of its proper divisors (430396).

491864 is a wasteful number, since it uses less digits than its factorization.

491864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 61489 (or 61485 counting only the distinct ones).

The product of its digits is 6912, while the sum is 32.

The square root of 491864 is about 701.3301647584. The cubic root of 491864 is about 78.9371930433.

The spelling of 491864 in words is "four hundred ninety-one thousand, eight hundred sixty-four".