66730240 has 72 divisors (see below), whose sum is σ = 164276280. Its totient is φ = 25952256.

The previous prime is 66730217. The next prime is 66730267. The reversal of 66730240 is 4203766.

It can be written as a sum of positive squares in 4 ways, for example, as 2985984 + 63744256 = 1728^2 + 7984^2 .

It is a junction number, because it is equal to n+sod(n) for n = 66730199 and 66730208.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 46656 + ... + 48064.

It is an arithmetic number, because the mean of its divisors is an integer number (2281615).

Almost surely, 2^66730240 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 66730240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (82138140).

66730240 is an abundant number, since it is smaller than the sum of its proper divisors (97546040).

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

66730240 is a wasteful number, since it uses less digits than its factorization.

66730240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1467 (or 1453 counting only the distinct ones).

The product of its (nonzero) digits is 6048, while the sum is 28.

The square root of 66730240 is about 8168.8579373129. The cubic root of 66730240 is about 405.6089807088.

The spelling of 66730240 in words is "sixty-six million, seven hundred thirty thousand, two hundred forty".