65680035840 has 780 divisors, whose sum is σ = 251936451756. Its totient is φ = 16364077056.

The previous prime is 65680035821. The next prime is 65680035847. The reversal of 65680035840 is 4853008656.

65680035840 is a `hidden beast` number, since 6 + 5 + 68 + 0 + 0 + 3 + 584 + 0 = 666.

It can be written as a sum of positive squares in 6 ways, for example, as 4619649024 + 61060386816 = 67968^2 + 247104^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65680035847) by changing a digit.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 479416252 + ... + 479416388.

Almost surely, 2^65680035840 is an apocalyptic number.

65680035840 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 65680035840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (125968225878).

65680035840 is an abundant number, since it is smaller than the sum of its proper divisors (186256415916).

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

65680035840 is a wasteful number, since it uses less digits than its factorization.

65680035840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 212 (or 164 counting only the distinct ones).

The product of its (nonzero) digits is 691200, while the sum is 45.

The spelling of 65680035840 in words is "sixty-five billion, six hundred eighty million, thirty-five thousand, eight hundred forty".