491004 has 36 divisors (see below), whose sum is σ = 1297296. Its totient is φ = 156288.

The previous prime is 491003. The next prime is 491039. The reversal of 491004 is 400194.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (491003) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 532 + ... + 1124.

It is an arithmetic number, because the mean of its divisors is an integer number (36036).

2⁴⁹¹⁰⁰⁴ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 491004, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (648648).

491004 is an abundant number, since it is smaller than the sum of its proper divisors (806292).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

491004 is a wasteful number, since it uses less digits than its factorization.

491004 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 626 (or 621 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

The square root of 491004 is about 700.7167758802. The cubic root of 491004 is about 78.8911602717.

Adding to 491004 its reverse (400194), we get a palindrome (891198).

The spelling of 491004 in words is "four hundred ninety-one thousand, four".