1761636257561 has 2 divisors, whose sum is σ = 1761636257562. Its totient is φ = 1761636257560.

The previous prime is 1761636257533. The next prime is 1761636257567. The reversal of 1761636257561 is 1657526361671.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1733527723225 + 28108534336 = 1316635^2 + 167656^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1761636257561 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1761636257497 and 1761636257506.

It is not a weakly prime, because it can be changed into another prime (1761636257567) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 880818128780 + 880818128781.

It is an arithmetic number, because the mean of its divisors is an integer number (880818128781).

Almost surely, 2^{1761636257561} is an apocalyptic number.

It is an amenable number.

1761636257561 is a deficient number, since it is larger than the sum of its proper divisors (1).

1761636257561 is an equidigital number, since it uses as much as digits as its factorization.

1761636257561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9525600, while the sum is 56.

The spelling of 1761636257561 in words is "one trillion, seven hundred sixty-one billion, six hundred thirty-six million, two hundred fifty-seven thousand, five hundred sixty-one".