65723640 has 64 divisors (see below), whose sum is σ = 200534400. Its totient is φ = 17227392.

The previous prime is 65723639. The next prime is 65723659. The reversal of 65723640 is 4632756.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2439 + ... + 11721.

It is an arithmetic number, because the mean of its divisors is an integer number (3133350).

Almost surely, 2^65723640 is an apocalyptic number.

65723640 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 65723640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (100267200).

65723640 is an abundant number, since it is smaller than the sum of its proper divisors (134810760).

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

65723640 is a wasteful number, since it uses less digits than its factorization.

65723640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9356 (or 9352 counting only the distinct ones).

The product of its (nonzero) digits is 30240, while the sum is 33.

The square root of 65723640 is about 8107.0117799347. The cubic root of 65723640 is about 403.5591537984.

The spelling of 65723640 in words is "sixty-five million, seven hundred twenty-three thousand, six hundred forty".