6661648 has 60 divisors (see below), whose sum is σ = 15584940. Its totient is φ = 2747136.

The previous prime is 6661643. The next prime is 6661649. The reversal of 6661648 is 8461666.

It can be written as a sum of positive squares in 2 ways, for example, as 5143824 + 1517824 = 2268^2 + 1232^2 .

It is not an unprimeable number, because it can be changed into a prime (6661643) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 22590 + ... + 22882.

It is an arithmetic number, because the mean of its divisors is an integer number (259749).

Almost surely, 2^6661648 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6661648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (7792470).

6661648 is an abundant number, since it is smaller than the sum of its proper divisors (8923292).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

6661648 is a wasteful number, since it uses less digits than its factorization.

6661648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 344 (or 331 counting only the distinct ones).

The product of its digits is 41472, while the sum is 37.

The square root of 6661648 is about 2581.0168538776. The cubic root of 6661648 is about 188.1599664588.

The spelling of 6661648 in words is "six million, six hundred sixty-one thousand, six hundred forty-eight".