6613661 has 4 divisors (see below), whose sum is σ = 6639072. Its totient is φ = 6588252.

The previous prime is 6613631. The next prime is 6613753. The reversal of 6613661 is 1663166.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1663166 = 2 ⋅831583.

It is a cyclic number.

It is not a de Polignac number, because 6613661 - 2⁶ = 6613597 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6613601) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 12311 + ... + 12836.

It is an arithmetic number, because the mean of its divisors is an integer number (1659768).

Almost surely, 2^6613661 is an apocalyptic number.

It is an amenable number.

6613661 is a deficient number, since it is larger than the sum of its proper divisors (25411).

6613661 is a wasteful number, since it uses less digits than its factorization.

6613661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25410.

The product of its digits is 3888, while the sum is 29.

The square root of 6613661 is about 2571.7039098621. The cubic root of 6613661 is about 187.7070755173.

The spelling of 6613661 in words is "six million, six hundred thirteen thousand, six hundred sixty-one".