491573 has 4 divisors (see below), whose sum is σ = 502080. Its totient is φ = 481068.

The previous prime is 491539. The next prime is 491581. The reversal of 491573 is 375194.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 375194 = 2 ⋅187597.

It is a cyclic number.

It is not a de Polignac number, because 491573 - 2¹⁰ = 490549 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (491503) 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, 5183 + ... + 5276.

It is an arithmetic number, because the mean of its divisors is an integer number (125520).

2⁴⁹¹⁵⁷³ is an apocalyptic number.

It is an amenable number.

491573 is a deficient number, since it is larger than the sum of its proper divisors (10507).

491573 is a wasteful number, since it uses less digits than its factorization.

491573 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10506.

The product of its digits is 3780, while the sum is 29.

The square root of 491573 is about 701.1226711496. The cubic root of 491573 is about 78.9216228487.

It can be divided in two parts, 49 and 1573, that multiplied together give a palindrome (77077).

The spelling of 491573 in words is "four hundred ninety-one thousand, five hundred seventy-three".