2688981 has 4 divisors (see below), whose sum is σ = 3585312. Its totient is φ = 1792652.

The previous prime is 2688979. The next prime is 2688997. The reversal of 2688981 is 1898862.

2688981 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 2688981 - 2¹ = 2688979 is a prime.

It is a super-2 number, since 2×2688981² = 14461237636722, which contains 22 as substring.

It is a D-number.

2688981 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2688181) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 448161 + ... + 448166.

It is an arithmetic number, because the mean of its divisors is an integer number (896328).

2^2688981 is an apocalyptic number.

It is an amenable number.

2688981 is a deficient number, since it is larger than the sum of its proper divisors (896331).

2688981 is an equidigital number, since it uses as much as digits as its factorization.

2688981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 896330.

The product of its digits is 55296, while the sum is 42.

The square root of 2688981 is about 1639.8112696283. The cubic root of 2688981 is about 139.0579783321.

The spelling of 2688981 in words is "two million, six hundred eighty-eight thousand, nine hundred eighty-one".