2506110781 has 2 divisors, whose sum is σ = 2506110782. Its totient is φ = 2506110780.

The previous prime is 2506110779. The next prime is 2506110787. The reversal of 2506110781 is 1870116052.

2506110781 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1764420025 + 741690756 = 42005^2 + 27234^2 .

It is a cyclic number.

It is not a de Polignac number, because 2506110781 - 2¹ = 2506110779 is a prime.

It is a super-2 number, since 2×2506110781² = 12561182493288859922, which contains 22 as substring.

Together with 2506110779, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2506110787) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1253055390 + 1253055391.

It is an arithmetic number, because the mean of its divisors is an integer number (1253055391).

Almost surely, 2^2506110781 is an apocalyptic number.

It is an amenable number.

2506110781 is a deficient number, since it is larger than the sum of its proper divisors (1).

2506110781 is an equidigital number, since it uses as much as digits as its factorization.

2506110781 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3360, while the sum is 31.

The square root of 2506110781 is about 50061.0705139233. The cubic root of 2506110781 is about 1358.3137226404.

The spelling of 2506110781 in words is "two billion, five hundred six million, one hundred ten thousand, seven hundred eighty-one".