2491307569 has 27 divisors (see below), whose sum is σ = 2740910571. Its totient is φ = 2264053680.

The previous prime is 2491307563. The next prime is 2491307587. The reversal of 2491307569 is 9657031942.

It is a happy number.

The square root of 2491307569 is 49913.

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

2491307569 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 2229256225 + 262051344 = 47215^2 + 16188^2 .

It is not a de Polignac number, because 2491307569 - 2¹⁵ = 2491274801 is a prime.

It is a super-2 number, since 2×2491307569² = 12413226806713379522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2491307563) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 35088804 + ... + 35088874.

Almost surely, 2^2491307569 is an apocalyptic number.

2491307569 is the 49913-rd square number.

2491307569 is the 24957-th centered octagonal number.

It is an amenable number.

2491307569 is a deficient number, since it is larger than the sum of its proper divisors (249603002).

2491307569 is an frugal number, since it uses more digits than its factorization.

2491307569 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 254 (or 127 counting only the distinct ones).

The product of its (nonzero) digits is 408240, while the sum is 46.

The cubic root of 2491307569 is about 1355.6339891613.

The spelling of 2491307569 in words is "two billion, four hundred ninety-one million, three hundred seven thousand, five hundred sixty-nine".