2785041781 has 2 divisors, whose sum is σ = 2785041782. Its totient is φ = 2785041780.

The previous prime is 2785041769. The next prime is 2785041817. The reversal of 2785041781 is 1871405872.

Together with next prime (2785041817) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2782035025 + 3006756 = 52745^2 + 1734^2 .

It is a cyclic number.

It is not a de Polignac number, because 2785041781 - 2⁷ = 2785041653 is a prime.

It is a super-2 number, since 2×2785041781² = 15512915443831303922, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2785048781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1392520890 + 1392520891.

It is an arithmetic number, because the mean of its divisors is an integer number (1392520891).

Almost surely, 2^2785041781 is an apocalyptic number.

It is an amenable number.

2785041781 is a deficient number, since it is larger than the sum of its proper divisors (1).

2785041781 is an equidigital number, since it uses as much as digits as its factorization.

2785041781 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 125440, while the sum is 43.

The square root of 2785041781 is about 52773.4950614416. The cubic root of 2785041781 is about 1406.9453818006.

The spelling of 2785041781 in words is "two billion, seven hundred eighty-five million, forty-one thousand, seven hundred eighty-one".