2780557 has 6 divisors (see below), whose sum is σ = 3011082. Its totient is φ = 2566512.

The previous prime is 2780527. The next prime is 2780597. The reversal of 2780557 is 7550872.

It can be written as a sum of positive squares in 3 ways, for example, as 175561 + 2604996 = 419^2 + 1614^2 .

It is a de Polignac number, because none of the positive numbers 2^k-2780557 is a prime.

It is the 1668-th Hogben number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2780507) by changing a digit.

It is a nontrivial repunit in base 1667.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 8058 + ... + 8395.

It is an arithmetic number, because the mean of its divisors is an integer number (501847).

2^2780557 is an apocalyptic number.

It is an amenable number.

2780557 is a deficient number, since it is larger than the sum of its proper divisors (230525).

2780557 is a wasteful number, since it uses less digits than its factorization.

2780557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16479 (or 16466 counting only the distinct ones).

The product of its (nonzero) digits is 19600, while the sum is 34.

The square root of 2780557 is about 1667.5002248875. The cubic root of 2780557 is about 140.6189769931.

The spelling of 2780557 in words is "two million, seven hundred eighty thousand, five hundred fifty-seven".