66561923948292 has 144 divisors (see below), whose sum is σ = 189851980211712. Its totient is φ = 19549267415040.

The previous prime is 66561923948243. The next prime is 66561923948357. The reversal of 66561923948292 is 29284932916566.

It is a happy number.

66561923948292 is a `hidden beast` number, since 6 + 6 + 5 + 61 + 9 + 239 + 48 + 292 = 666.

66561923948292 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a self number, because there is not a number n which added to its sum of digits gives 66561923948292.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 49644309 + ... + 50967452.

It is an arithmetic number, because the mean of its divisors is an integer number (1318416529248).

Almost surely, 2^{66561923948292} is an apocalyptic number.

It is an amenable number.

66561923948292 is an abundant number, since it is smaller than the sum of its proper divisors (123290056263420).

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

66561923948292 is a wasteful number, since it uses less digits than its factorization.

66561923948292 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 100611858 (or 100611853 counting only the distinct ones).

The product of its digits is 604661760, while the sum is 72.

The spelling of 66561923948292 in words is "sixty-six trillion, five hundred sixty-one billion, nine hundred twenty-three million, nine hundred forty-eight thousand, two hundred ninety-two".