66507294672 has 450 divisors, whose sum is σ = 242507168838. Its totient is φ = 17537554944.

The previous prime is 66507294643. The next prime is 66507294691. The reversal of 66507294672 is 27649270566.

66507294672 is a `hidden beast` number, since 6 + 6 + 507 + 29 + 46 + 72 = 666.

It can be written as a sum of positive squares in 3 ways, for example, as 178382736 + 66328911936 = 13356^2 + 257544^2 .

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

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 89 ways as a sum of consecutive naturals, for example, 10729078 + ... + 10735274.

Almost surely, 2^66507294672 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66507294672, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (121253584419).

66507294672 is an abundant number, since it is smaller than the sum of its proper divisors (175999874166).

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

66507294672 is a wasteful number, since it uses less digits than its factorization.

66507294672 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6257 (or 6222 counting only the distinct ones).

The product of its (nonzero) digits is 7620480, while the sum is 54.

The spelling of 66507294672 in words is "sixty-six billion, five hundred seven million, two hundred ninety-four thousand, six hundred seventy-two".