65681719722 has 64 divisors (see below), whose sum is σ = 149418741120. Its totient is φ = 21375446400.

The previous prime is 65681719703. The next prime is 65681719751. The reversal of 65681719722 is 22791718656.

65681719722 is a `hidden beast` number, since 6 + 568 + 1 + 7 + 1 + 9 + 72 + 2 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 7103022 + ... + 7112262.

It is an arithmetic number, because the mean of its divisors is an integer number (2334667830).

Almost surely, 2^65681719722 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 65681719722, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (74709370560).

65681719722 is an abundant number, since it is smaller than the sum of its proper divisors (83737021398).

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

65681719722 is a wasteful number, since it uses less digits than its factorization.

65681719722 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12356 (or 12350 counting only the distinct ones).

The product of its digits is 2540160, while the sum is 54.

The spelling of 65681719722 in words is "sixty-five billion, six hundred eighty-one million, seven hundred nineteen thousand, seven hundred twenty-two".