6551661 has 8 divisors (see below), whose sum is σ = 8751744. Its totient is φ = 4359680.

The previous prime is 6551653. The next prime is 6551689. The reversal of 6551661 is 1661556.

6551661 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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 6551661 - 2³ = 6551653 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6551161) 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, 220 + ... + 3626.

It is an arithmetic number, because the mean of its divisors is an integer number (1093968).

Almost surely, 2^6551661 is an apocalyptic number.

It is an amenable number.

6551661 is a deficient number, since it is larger than the sum of its proper divisors (2200083).

6551661 is a wasteful number, since it uses less digits than its factorization.

6551661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4051.

The product of its digits is 5400, while the sum is 30.

The square root of 6551661 is about 2559.6212610463. The cubic root of 6551661 is about 187.1186774668.

The spelling of 6551661 in words is "six million, five hundred fifty-one thousand, six hundred sixty-one".