2688391 has 2 divisors, whose sum is σ = 2688392. Its totient is φ = 2688390.

The previous prime is 2688377. The next prime is 2688419. The reversal of 2688391 is 1938862.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 2688391 - 2⁹ = 2687879 is a prime.

2688391 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 2688391.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2682391) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1344195 + 1344196.

It is an arithmetic number, because the mean of its divisors is an integer number (1344196).

2^2688391 is an apocalyptic number.

2688391 is a deficient number, since it is larger than the sum of its proper divisors (1).

2688391 is an equidigital number, since it uses as much as digits as its factorization.

2688391 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 20736, while the sum is 37.

The square root of 2688391 is about 1639.6313610077. The cubic root of 2688391 is about 139.0478071671.

The spelling of 2688391 in words is "two million, six hundred eighty-eight thousand, three hundred ninety-one".