2851991 has 2 divisors, whose sum is σ = 2851992. Its totient is φ = 2851990.

The previous prime is 2851973. The next prime is 2852027. The reversal of 2851991 is 1991582.

2851991 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2851991 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2851921) 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 as a sum of consecutive naturals, namely, 1425995 + 1425996.

It is an arithmetic number, because the mean of its divisors is an integer number (1425996).

2^2851991 is an apocalyptic number.

2851991 is a deficient number, since it is larger than the sum of its proper divisors (1).

2851991 is an equidigital number, since it uses as much as digits as its factorization.

2851991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6480, while the sum is 35.

The square root of 2851991 is about 1688.7838819695. The cubic root of 2851991 is about 141.8130018853.

The spelling of 2851991 in words is "two million, eight hundred fifty-one thousand, nine hundred ninety-one".