10661566516601 has 64 divisors (see below), whose sum is σ = 15105051279360. Its totient is φ = 7252819453440.

The previous prime is 10661566516547. The next prime is 10661566516607.

10661566516601 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 10661566516601 - 2¹⁸ = 10661566254457 is a prime.

It is a super-2 number, since 2×10661566516601² (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 10661566516601.

It is not an unprimeable number, because it can be changed into a prime (10661566516607) by changing a digit.

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 63 ways as a sum of consecutive naturals, for example, 552545 + ... + 4650638.

It is an arithmetic number, because the mean of its divisors is an integer number (236016426240).

Almost surely, 2^{10661566516601} is an apocalyptic number.

10661566516601 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

10661566516601 is a deficient number, since it is larger than the sum of its proper divisors (4443484762759).

10661566516601 is a wasteful number, since it uses less digits than its factorization.

10661566516601 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5203326.

The product of its (nonzero) digits is 1166400, while the sum is 50.

The spelling of 10661566516601 in words is "ten trillion, six hundred sixty-one billion, five hundred sixty-six million, five hundred sixteen thousand, six hundred one".