6656660661 has 8 divisors (see below), whose sum is σ = 10143482944. Its totient is φ = 3803806080.

The previous prime is 6656660653. The next prime is 6656660669. The reversal of 6656660661 is 1660666566.

6656660661 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (6656660653) and next prime (6656660669).

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

It is not a de Polignac number, because 6656660661 - 2³ = 6656660653 is a prime.

It is a super-2 number, since 2×6656660661² = 88622262311409913842, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 6656660661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6656660669) 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, 158491900 + ... + 158491941.

It is an arithmetic number, because the mean of its divisors is an integer number (1267935368).

Almost surely, 2^6656660661 is an apocalyptic number.

It is an amenable number.

6656660661 is a deficient number, since it is larger than the sum of its proper divisors (3486822283).

6656660661 is a wasteful number, since it uses less digits than its factorization.

6656660661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 316983851.

The product of its (nonzero) digits is 1399680, while the sum is 48.

The square root of 6656660661 is about 81588.3610633281. The cubic root of 6656660661 is about 1881.1299851018.

The spelling of 6656660661 in words is "six billion, six hundred fifty-six million, six hundred sixty thousand, six hundred sixty-one".