65666616480 has 72 divisors (see below), whose sum is σ = 224087333652. Its totient is φ = 17511097344.

The previous prime is 65666616461. The next prime is 65666616487. The reversal of 65666616480 is 8461666656.

It can be written as a sum of positive squares in 2 ways, for example, as 65619994896 + 46621584 = 256164^2 + 6828^2 .

It is a tau number, because it is divible by the number of its divisors (72).

It is not an unprimeable number, because it can be changed into a prime (65666616487) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 22799469 + ... + 22802348.

Almost surely, 2^65666616480 is an apocalyptic number.

65666616480 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

65666616480 is an abundant number, since it is smaller than the sum of its proper divisors (158420717172).

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

65666616480 is a wasteful number, since it uses less digits than its factorization.

65666616480 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45601838 (or 45601827 counting only the distinct ones).

The product of its (nonzero) digits is 7464960, while the sum is 54.

The spelling of 65666616480 in words is "sixty-five billion, six hundred sixty-six million, six hundred sixteen thousand, four hundred eighty".