491578 has 4 divisors (see below), whose sum is σ = 737370. Its totient is φ = 245788.

The previous prime is 491539. The next prime is 491581. The reversal of 491578 is 875194.

It is a happy number.

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

It can be written as a sum of positive squares in only one way, i.e., 380689 + 110889 = 617^2 + 333^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 122893 + ... + 122896.

2⁴⁹¹⁵⁷⁸ is an apocalyptic number.

491578 is a deficient number, since it is larger than the sum of its proper divisors (245792).

491578 is a wasteful number, since it uses less digits than its factorization.

491578 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 245791.

The product of its digits is 10080, while the sum is 34.

The square root of 491578 is about 701.1262368504. The cubic root of 491578 is about 78.9218904297.

The spelling of 491578 in words is "four hundred ninety-one thousand, five hundred seventy-eight".