11661066556631 has 2 divisors, whose sum is σ = 11661066556632. Its totient is φ = 11661066556630.

The previous prime is 11661066556609. The next prime is 11661066556637. The reversal of 11661066556631 is 13665566016611.

It is a strong prime.

It is an emirp because it is prime and its reverse (13665566016611) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11661066556631 is a prime.

It is a super-2 number, since 2×11661066556631² (a number of 27 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11661066556637) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5830533278315 + 5830533278316.

It is an arithmetic number, because the mean of its divisors is an integer number (5830533278316).

Almost surely, 2^{11661066556631} is an apocalyptic number.

11661066556631 is a deficient number, since it is larger than the sum of its proper divisors (1).

11661066556631 is an equidigital number, since it uses as much as digits as its factorization.

11661066556631 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3499200, while the sum is 53.

The spelling of 11661066556631 in words is "eleven trillion, six hundred sixty-one billion, sixty-six million, five hundred fifty-six thousand, six hundred thirty-one".