66825220164 has 24 divisors (see below), whose sum is σ = 158121649728. Its totient is φ = 21961339680.

The previous prime is 66825220139. The next prime is 66825220213. The reversal of 66825220164 is 46102252866.

It is a happy number.

It is a super-2 number, since 2×66825220164² (a number of 22 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 39215827 + ... + 39217530.

It is an arithmetic number, because the mean of its divisors is an integer number (6588402072).

Almost surely, 2^66825220164 is an apocalyptic number.

It is an amenable number.

66825220164 is an abundant number, since it is smaller than the sum of its proper divisors (91296429564).

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

66825220164 is a wasteful number, since it uses less digits than its factorization.

66825220164 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 78433435 (or 78433433 counting only the distinct ones).

The product of its (nonzero) digits is 276480, while the sum is 42.

The spelling of 66825220164 in words is "sixty-six billion, eight hundred twenty-five million, two hundred twenty thousand, one hundred sixty-four".