1006561516691 has 2 divisors, whose sum is σ = 1006561516692. Its totient is φ = 1006561516690.

The previous prime is 1006561516621. The next prime is 1006561516747. The reversal of 1006561516691 is 1966151656001.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1006561516691 - 2³⁰ = 1005487774867 is a prime.

It is not a weakly prime, because it can be changed into another prime (1006561516621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 503280758345 + 503280758346.

It is an arithmetic number, because the mean of its divisors is an integer number (503280758346).

Almost surely, 2^{1006561516691} is an apocalyptic number.

1006561516691 is a deficient number, since it is larger than the sum of its proper divisors (1).

1006561516691 is an equidigital number, since it uses as much as digits as its factorization.

1006561516691 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 291600, while the sum is 47.

The spelling of 1006561516691 in words is "one trillion, six billion, five hundred sixty-one million, five hundred sixteen thousand, six hundred ninety-one".