10661555666 has 8 divisors (see below), whose sum is σ = 16046915724. Its totient is φ = 5312583760.

The previous prime is 10661555659. The next prime is 10661555683. The reversal of 10661555666 is 66655516601.

It can be written as a sum of positive squares in 2 ways, for example, as 10633940641 + 27615025 = 103121^2 + 5255^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×10661555666² (a number of 21 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 10661555666.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9096305 + ... + 9097476.

Almost surely, 2^10661555666 is an apocalyptic number.

10661555666 is a deficient number, since it is larger than the sum of its proper divisors (5385360058).

10661555666 is a wasteful number, since it uses less digits than its factorization.

10661555666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18194076.

The product of its (nonzero) digits is 972000, while the sum is 47.

The spelling of 10661555666 in words is "ten billion, six hundred sixty-one million, five hundred fifty-five thousand, six hundred sixty-six".