661106165109 has 8 divisors (see below), whose sum is σ = 949280647392. Its totient is φ = 406834563120.

The previous prime is 661106165089. The next prime is 661106165113. The reversal of 661106165109 is 901561601166.

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

It is not a de Polignac number, because 661106165109 - 2⁷ = 661106164981 is a prime.

It is a super-2 number, since 2×661106165109² (a number of 24 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661106155109) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8475720027 + ... + 8475720104.

It is an arithmetic number, because the mean of its divisors is an integer number (118660080924).

Almost surely, 2^661106165109 is an apocalyptic number.

It is an amenable number.

661106165109 is a deficient number, since it is larger than the sum of its proper divisors (288174482283).

661106165109 is a wasteful number, since it uses less digits than its factorization.

661106165109 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16951440147.

The product of its (nonzero) digits is 58320, while the sum is 42.

The spelling of 661106165109 in words is "six hundred sixty-one billion, one hundred six million, one hundred sixty-five thousand, one hundred nine".