6615861 has 16 divisors (see below), whose sum is σ = 10297344. Its totient is φ = 3699504.

The previous prime is 6615853. The next prime is 6615887. The reversal of 6615861 is 1685166.

It is not a de Polignac number, because 6615861 - 2³ = 6615853 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6615361) 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 15 ways as a sum of consecutive naturals, for example, 2365 + ... + 4338.

It is an arithmetic number, because the mean of its divisors is an integer number (643584).

Almost surely, 2^6615861 is an apocalyptic number.

It is an amenable number.

6615861 is a deficient number, since it is larger than the sum of its proper divisors (3681483).

6615861 is a wasteful number, since it uses less digits than its factorization.

6615861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6760.

The product of its digits is 8640, while the sum is 33.

The square root of 6615861 is about 2572.1316062752. The cubic root of 6615861 is about 187.7278864714.

The spelling of 6615861 in words is "six million, six hundred fifteen thousand, eight hundred sixty-one".