2666005681 has 8 divisors (see below), whose sum is σ = 2674516320. Its totient is φ = 2657506752.

The previous prime is 2666005663. The next prime is 2666005709. The reversal of 2666005681 is 1865006662.

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

It is a cyclic number.

It is not a de Polignac number, because 2666005681 - 2⁵ = 2666005649 is a prime.

It is a super-2 number, since 2×2666005681² = 14215172582248547522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2666005631) 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, 699126 + ... + 702928.

It is an arithmetic number, because the mean of its divisors is an integer number (334314540).

Almost surely, 2^2666005681 is an apocalyptic number.

It is an amenable number.

2666005681 is a deficient number, since it is larger than the sum of its proper divisors (8510639).

2666005681 is a wasteful number, since it uses less digits than its factorization.

2666005681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5855.

The product of its (nonzero) digits is 103680, while the sum is 40.

The square root of 2666005681 is about 51633.3775865961. The cubic root of 2666005681 is about 1386.6079637673.

The spelling of 2666005681 in words is "two billion, six hundred sixty-six million, five thousand, six hundred eighty-one".