11661066556637 has 2 divisors, whose sum is σ = 11661066556638. Its totient is φ = 11661066556636.

The previous prime is 11661066556631. The next prime is 11661066556651. The reversal of 11661066556637 is 73665566016611.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7574709423961 + 4086357132676 = 2752219^2 + 2021474^2 .

It is a cyclic number.

It is not a de Polignac number, because 11661066556637 - 2²⁰ = 11661065508061 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11661066556631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5830533278318 + 5830533278319.

It is an arithmetic number, because the mean of its divisors is an integer number (5830533278319).

Almost surely, 2^{11661066556637} is an apocalyptic number.

It is an amenable number.

11661066556637 is a deficient number, since it is larger than the sum of its proper divisors (1).

11661066556637 is an equidigital number, since it uses as much as digits as its factorization.

11661066556637 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 24494400, while the sum is 59.

The spelling of 11661066556637 in words is "eleven trillion, six hundred sixty-one billion, sixty-six million, five hundred fifty-six thousand, six hundred thirty-seven".