2688408491 has 4 divisors (see below), whose sum is σ = 2713533912. Its totient is φ = 2663283072.

The previous prime is 2688408487. The next prime is 2688408511. The reversal of 2688408491 is 1948048862.

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

It is not a de Polignac number, because 2688408491 - 2² = 2688408487 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2688408421) 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, 12562550 + ... + 12562763.

It is an arithmetic number, because the mean of its divisors is an integer number (678383478).

Almost surely, 2^2688408491 is an apocalyptic number.

2688408491 is a deficient number, since it is larger than the sum of its proper divisors (25125421).

2688408491 is a wasteful number, since it uses less digits than its factorization.

2688408491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25125420.

The product of its (nonzero) digits is 884736, while the sum is 50.

The square root of 2688408491 is about 51849.8649082136. The cubic root of 2688408491 is about 1390.4810872045.

The spelling of 2688408491 in words is "two billion, six hundred eighty-eight million, four hundred eight thousand, four hundred ninety-one".