491198569 has 9 divisors (see below), whose sum is σ = 505677207. Its totient is φ = 477125064.

The previous prime is 491198563. The next prime is 491198593. The reversal of 491198569 is 965891194.

It is a happy number.

The square root of 491198569 is 22163.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 439531225 + 51667344 = 20965^2 + 7188^2 .

It is not a de Polignac number, because 491198569 - 2²³ = 482809961 is a prime.

It is a super-2 number, since 2×491198569² = 482552068375295522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (491198563) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 819732 + ... + 820330.

Almost surely, 2^491198569 is an apocalyptic number.

491198569 is the 22163-rd square number.

491198569 is the 11082-nd centered octagonal number.

It is an amenable number.

491198569 is a deficient number, since it is larger than the sum of its proper divisors (14478638).

491198569 is an frugal number, since it uses more digits than its factorization.

491198569 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1272 (or 636 counting only the distinct ones).

The product of its digits is 699840, while the sum is 52.

The cubic root of 491198569 is about 789.0157956703.

The spelling of 491198569 in words is "four hundred ninety-one million, one hundred ninety-eight thousand, five hundred sixty-nine".