660265720 has 64 divisors (see below), whose sum is σ = 1576584000. Its totient is φ = 248002560.

The previous prime is 660265717. The next prime is 660265733. The reversal of 660265720 is 27562066.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (34).

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, 406510 + ... + 408130.

It is an arithmetic number, because the mean of its divisors is an integer number (24634125).

Almost surely, 2^660265720 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 660265720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (788292000).

660265720 is an abundant number, since it is smaller than the sum of its proper divisors (916318280).

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

660265720 is a wasteful number, since it uses less digits than its factorization.

660265720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2248 (or 2244 counting only the distinct ones).

The product of its (nonzero) digits is 30240, while the sum is 34.

The square root of 660265720 is about 25695.6362053949. The cubic root of 660265720 is about 870.7755976059.

The spelling of 660265720 in words is "six hundred sixty million, two hundred sixty-five thousand, seven hundred twenty".