65785440 has 144 divisors (see below), whose sum is σ = 241142832. Its totient is φ = 15031296.

The previous prime is 65785439. The next prime is 65785457. The reversal of 65785440 is 4458756.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 22122 + ... + 24918.

It is an arithmetic number, because the mean of its divisors is an integer number (1674603).

Almost surely, 2^65785440 is an apocalyptic number.

65785440 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 65785440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (120571416).

65785440 is an abundant number, since it is smaller than the sum of its proper divisors (175357392).

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

65785440 is a wasteful number, since it uses less digits than its factorization.

65785440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2829 (or 2814 counting only the distinct ones).

The product of its (nonzero) digits is 134400, while the sum is 39.

The square root of 65785440 is about 8110.8223997323. The cubic root of 65785440 is about 403.6856031894.

The spelling of 65785440 in words is "sixty-five million, seven hundred eighty-five thousand, four hundred forty".