11505561006566 has 48 divisors (see below), whose sum is σ = 19461092691600. Its totient is φ = 5095989940800.

The previous prime is 11505561006547. The next prime is 11505561006587. The reversal of 11505561006566 is 66560016550511.

It is a super-2 number, since 2×11505561006566² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 11505561006566.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2062541 + ... + 5221608.

It is an arithmetic number, because the mean of its divisors is an integer number (405439431075).

Almost surely, 2^{11505561006566} is an apocalyptic number.

11505561006566 is a deficient number, since it is larger than the sum of its proper divisors (7955531685034).

11505561006566 is a wasteful number, since it uses less digits than its factorization.

11505561006566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7284341 (or 7284330 counting only the distinct ones).

The product of its (nonzero) digits is 810000, while the sum is 47.

The spelling of 11505561006566 in words is "eleven trillion, five hundred five billion, five hundred sixty-one million, six thousand, five hundred sixty-six".