2778081 has 4 divisors (see below), whose sum is σ = 3704112. Its totient is φ = 1852052.

The previous prime is 2778079. The next prime is 2778091. The reversal of 2778081 is 1808772.

2778081 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 2778081 - 2¹ = 2778079 is a prime.

It is a super-2 number, since 2×2778081² = 15435468085122, which contains 22 as substring.

It is a D-number.

2778081 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (2778011) 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, 463011 + ... + 463016.

It is an arithmetic number, because the mean of its divisors is an integer number (926028).

2^2778081 is an apocalyptic number.

It is an amenable number.

2778081 is a deficient number, since it is larger than the sum of its proper divisors (926031).

2778081 is an equidigital number, since it uses as much as digits as its factorization.

2778081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 926030.

The product of its (nonzero) digits is 6272, while the sum is 33.

The square root of 2778081 is about 1666.7576308510. The cubic root of 2778081 is about 140.5772256481.

The spelling of 2778081 in words is "two million, seven hundred seventy-eight thousand, eighty-one".