65721736080 has 960 divisors, whose sum is σ = 302555635200. Its totient is φ = 12599193600.

The previous prime is 65721736057. The next prime is 65721736099. The reversal of 65721736080 is 8063712756.

65721736080 is a `hidden beast` number, since 6 + 572 + 1 + 73 + 6 + 0 + 8 + 0 = 666.

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

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 191 ways as a sum of consecutive naturals, for example, 35314350 + ... + 35316210.

It is an arithmetic number, because the mean of its divisors is an integer number (315162120).

Almost surely, 2^65721736080 is an apocalyptic number.

65721736080 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 65721736080, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (151277817600).

65721736080 is an abundant number, since it is smaller than the sum of its proper divisors (236833899120).

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

65721736080 is a wasteful number, since it uses less digits than its factorization.

65721736080 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1925 (or 1902 counting only the distinct ones).

The product of its (nonzero) digits is 423360, while the sum is 45.

The spelling of 65721736080 in words is "sixty-five billion, seven hundred twenty-one million, seven hundred thirty-six thousand, eighty".