66508440161388 has 96 divisors (see below), whose sum is σ = 164439824629248. Its totient is φ = 20849544115200.

The previous prime is 66508440161351. The next prime is 66508440161389. The reversal of 66508440161388 is 88316104480566.

It is a happy number.

It is a super-2 number, since 2×66508440161388² (a number of 28 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (66508440161389) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1735723206 + ... + 1735761522.

It is an arithmetic number, because the mean of its divisors is an integer number (1712914839888).

Almost surely, 2^{66508440161388} is an apocalyptic number.

66508440161388 is a gapful number since it is divisible by the number (68) formed by its first and last digit.

It is an amenable number.

66508440161388 is an abundant number, since it is smaller than the sum of its proper divisors (97931384467860).

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

66508440161388 is a wasteful number, since it uses less digits than its factorization.

66508440161388 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44583 (or 44581 counting only the distinct ones).

The product of its (nonzero) digits is 26542080, while the sum is 60.

The spelling of 66508440161388 in words is "sixty-six trillion, five hundred eight billion, four hundred forty million, one hundred sixty-one thousand, three hundred eighty-eight".