1611165666 has 64 divisors (see below), whose sum is σ = 3726913536. Its totient is φ = 459691200.

The previous prime is 1611165653. The next prime is 1611165671. The reversal of 1611165666 is 6665611161.

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 31 ways as a sum of consecutive naturals, for example, 65061 + ... + 86343.

It is an arithmetic number, because the mean of its divisors is an integer number (58233024).

Almost surely, 2^1611165666 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1611165666, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1863456768).

1611165666 is an abundant number, since it is smaller than the sum of its proper divisors (2115747870).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1611165666 is a wasteful number, since it uses less digits than its factorization.

1611165666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21367.

The product of its digits is 38880, while the sum is 39.

The square root of 1611165666 is about 40139.3281707604. The cubic root of 1611165666 is about 1172.3215079498.

The spelling of 1611165666 in words is "one billion, six hundred eleven million, one hundred sixty-five thousand, six hundred sixty-six".