66251168520 has 64 divisors (see below), whose sum is σ = 210444894720. Its totient is φ = 16627743744.

The previous prime is 66251168513. The next prime is 66251168531. The reversal of 66251168520 is 2586115266.

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 15 ways as a sum of consecutive naturals, for example, 16235992 + ... + 16240071.

It is an arithmetic number, because the mean of its divisors is an integer number (3288201480).

Almost surely, 2^66251168520 is an apocalyptic number.

66251168520 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

66251168520 is an abundant number, since it is smaller than the sum of its proper divisors (144193726200).

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

66251168520 is a wasteful number, since it uses less digits than its factorization.

66251168520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32476094 (or 32476090 counting only the distinct ones).

The product of its (nonzero) digits is 172800, while the sum is 42.

The spelling of 66251168520 in words is "sixty-six billion, two hundred fifty-one million, one hundred sixty-eight thousand, five hundred twenty".