10001561666 has 8 divisors (see below), whose sum is σ = 15002766864. Its totient is φ = 5000639380.

The previous prime is 10001561629. The next prime is 10001561681. The reversal of 10001561666 is 66616510001.

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 103001 + ... + 174963.

It is an arithmetic number, because the mean of its divisors is an integer number (1875345858).

Almost surely, 2^10001561666 is an apocalyptic number.

10001561666 is a deficient number, since it is larger than the sum of its proper divisors (5001205198).

10001561666 is an equidigital number, since it uses as much as digits as its factorization.

10001561666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 141456.

The product of its (nonzero) digits is 6480, while the sum is 32.

The spelling of 10001561666 in words is "ten billion, one million, five hundred sixty-one thousand, six hundred sixty-six".