2681991 has 28 divisors (see below), whose sum is σ = 4345768. Its totient is φ = 1644624.

The previous prime is 2681989. The next prime is 2681993. The reversal of 2681991 is 1991862.

2681991 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (2681989) and next prime (2681993).

It is not a de Polignac number, because 2681991 - 2¹ = 2681989 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2681993) 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 27 ways as a sum of consecutive naturals, for example, 9336 + ... + 9618.

It is an arithmetic number, because the mean of its divisors is an integer number (155206).

2^2681991 is an apocalyptic number.

2681991 is a deficient number, since it is larger than the sum of its proper divisors (1663777).

2681991 is an equidigital number, since it uses as much as digits as its factorization.

2681991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 314 (or 299 counting only the distinct ones).

The product of its digits is 7776, while the sum is 36.

The square root of 2681991 is about 1637.6785398850. The cubic root of 2681991 is about 138.9373801405.

The spelling of 2681991 in words is "two million, six hundred eighty-one thousand, nine hundred ninety-one".