2780145 has 12 divisors (see below), whose sum is σ = 4818996. Its totient is φ = 1482720.

The previous prime is 2780131. The next prime is 2780149. The reversal of 2780145 is 5410872.

It can be written as a sum of positive squares in 2 ways, for example, as 374544 + 2405601 = 612^2 + 1551^2 .

It is not a de Polignac number, because 2780145 - 2⁹ = 2779633 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2780149) 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 in 11 ways as a sum of consecutive naturals, for example, 30846 + ... + 30935.

It is an arithmetic number, because the mean of its divisors is an integer number (401583).

2^2780145 is an apocalyptic number.

It is an amenable number.

2780145 is a deficient number, since it is larger than the sum of its proper divisors (2038851).

2780145 is a wasteful number, since it uses less digits than its factorization.

2780145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61792 (or 61789 counting only the distinct ones).

The product of its (nonzero) digits is 2240, while the sum is 27.

The square root of 2780145 is about 1667.3766820968. The cubic root of 2780145 is about 140.6120313966.

The spelling of 2780145 in words is "two million, seven hundred eighty thousand, one hundred forty-five".