2788021 has 2 divisors, whose sum is σ = 2788022. Its totient is φ = 2788020.

The previous prime is 2788007. The next prime is 2788033. The reversal of 2788021 is 1208872.

2788021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1653796 + 1134225 = 1286^2 + 1065^2 .

It is a cyclic number.

It is not a de Polignac number, because 2788021 - 2¹¹ = 2785973 is a prime.

It is a super-2 number, since 2×2788021² = 15546122192882, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2788081) 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, 1394010 + 1394011.

It is an arithmetic number, because the mean of its divisors is an integer number (1394011).

2^2788021 is an apocalyptic number.

It is an amenable number.

2788021 is a deficient number, since it is larger than the sum of its proper divisors (1).

2788021 is an equidigital number, since it uses as much as digits as its factorization.

2788021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1792, while the sum is 28.

The square root of 2788021 is about 1669.7368056074. The cubic root of 2788021 is about 140.7446882917.

The spelling of 2788021 in words is "two million, seven hundred eighty-eight thousand, twenty-one".