2781058158661 has 2 divisors, whose sum is σ = 2781058158662. Its totient is φ = 2781058158660.

The previous prime is 2781058158617. The next prime is 2781058158667. The reversal of 2781058158661 is 1668518501872.

2781058158661 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2037270928900 + 743787229761 = 1427330^2 + 862431^2 .

It is a cyclic number.

It is not a de Polignac number, because 2781058158661 - 2²⁵ = 2781024604229 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2781058158596 and 2781058158605.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2781058158667) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1390529079330 + 1390529079331.

It is an arithmetic number, because the mean of its divisors is an integer number (1390529079331).

Almost surely, 2^{2781058158661} is an apocalyptic number.

It is an amenable number.

2781058158661 is a deficient number, since it is larger than the sum of its proper divisors (1).

2781058158661 is an equidigital number, since it uses as much as digits as its factorization.

2781058158661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6451200, while the sum is 58.

The spelling of 2781058158661 in words is "two trillion, seven hundred eighty-one billion, fifty-eight million, one hundred fifty-eight thousand, six hundred sixty-one".