2780874781 has 2 divisors, whose sum is σ = 2780874782. Its totient is φ = 2780874780.

The previous prime is 2780874737. The next prime is 2780874787. The reversal of 2780874781 is 1874780872.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2780874756 + 25 = 52734^2 + 5^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2780874781 is a prime.

It is a super-2 number, since 2×2780874781² = 15466529095203595922, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2780874787) 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, 1390437390 + 1390437391.

It is an arithmetic number, because the mean of its divisors is an integer number (1390437391).

Almost surely, 2^2780874781 is an apocalyptic number.

It is an amenable number.

2780874781 is a deficient number, since it is larger than the sum of its proper divisors (1).

2780874781 is an equidigital number, since it uses as much as digits as its factorization.

2780874781 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1404928, while the sum is 52.

The square root of 2780874781 is about 52734.0002370387. Note that the first 3 decimals coincide. The cubic root of 2780874781 is about 1406.2433375395.

The spelling of 2780874781 in words is "two billion, seven hundred eighty million, eight hundred seventy-four thousand, seven hundred eighty-one".