660705280 has 52 divisors (see below), whose sum is σ = 1585548252. Its totient is φ = 264273920.

The previous prime is 660705251. The next prime is 660705293. The reversal of 660705280 is 82507066.

It can be written as a sum of positive squares in 2 ways, for example, as 138674176 + 522031104 = 11776^2 + 22848^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4350 + ... + 36610.

Almost surely, 2^660705280 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 660705280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (792774126).

660705280 is an abundant number, since it is smaller than the sum of its proper divisors (924842972).

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

660705280 is an equidigital number, since it uses as much as digits as its factorization.

660705280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32290 (or 32268 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 34.

The square root of 660705280 is about 25704.1879856182. The cubic root of 660705280 is about 870.9687891263.

The spelling of 660705280 in words is "six hundred sixty million, seven hundred five thousand, two hundred eighty".