2778091 has 2 divisors, whose sum is σ = 2778092. Its totient is φ = 2778090.

The previous prime is 2778079. The next prime is 2778107. The reversal of 2778091 is 1908772.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 2778091 - 2¹⁹ = 2253803 is a prime.

It is not a weakly prime, because it can be changed into another prime (2778011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1389045 + 1389046.

It is an arithmetic number, because the mean of its divisors is an integer number (1389046).

2^2778091 is an apocalyptic number.

2778091 is a deficient number, since it is larger than the sum of its proper divisors (1).

2778091 is an equidigital number, since it uses as much as digits as its factorization.

2778091 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7056, while the sum is 34.

The square root of 2778091 is about 1666.7606306846. The cubic root of 2778091 is about 140.5773943221.

The spelling of 2778091 in words is "two million, seven hundred seventy-eight thousand, ninety-one".