661105105666 has 8 divisors (see below), whose sum is σ = 1012756757760. Its totient is φ = 323519519748.

The previous prime is 661105105627. The next prime is 661105105673. The reversal of 661105105666 is 666501501166.

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

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, 3516516426 + ... + 3516516613.

It is an arithmetic number, because the mean of its divisors is an integer number (126594594720).

Almost surely, 2^661105105666 is an apocalyptic number.

661105105666 is a deficient number, since it is larger than the sum of its proper divisors (351651652094).

661105105666 is a wasteful number, since it uses less digits than its factorization.

661105105666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7033033088.

The product of its (nonzero) digits is 194400, while the sum is 43.

The spelling of 661105105666 in words is "six hundred sixty-one billion, one hundred five million, one hundred five thousand, six hundred sixty-six".