65785720 has 256 divisors, whose sum is σ = 209018880. Its totient is φ = 17971200.

The previous prime is 65785697. The next prime is 65785723. The reversal of 65785720 is 2758756.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65785723) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1241214 + ... + 1241266.

It is an arithmetic number, because the mean of its divisors is an integer number (816480).

Almost surely, 2^65785720 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 65785720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (104509440).

65785720 is an abundant number, since it is smaller than the sum of its proper divisors (143233160).

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

65785720 is a wasteful number, since it uses less digits than its factorization.

65785720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 126 (or 122 counting only the distinct ones).

The product of its (nonzero) digits is 117600, while the sum is 40.

The square root of 65785720 is about 8110.8396606023. The cubic root of 65785720 is about 403.6861759191.

The spelling of 65785720 in words is "sixty-five million, seven hundred eighty-five thousand, seven hundred twenty".