6661280 has 96 divisors (see below), whose sum is σ = 17418240. Its totient is φ = 2396160.

The previous prime is 6661279. The next prime is 6661301. The reversal of 6661280 is 821666.

6661280 = T₆₄₀ + T₆₄₁ + ... + T₆₇₀.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 84281 + ... + 84359.

It is an arithmetic number, because the mean of its divisors is an integer number (181440).

Almost surely, 2^6661280 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 6661280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (8709120).

6661280 is an abundant number, since it is smaller than the sum of its proper divisors (10756960).

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

6661280 is a wasteful number, since it uses less digits than its factorization.

6661280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 142 (or 134 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 29.

The square root of 6661280 is about 2580.9455631609. The cubic root of 6661280 is about 188.1565016434.

The spelling of 6661280 in words is "six million, six hundred sixty-one thousand, two hundred eighty".