66344725440 has 504 divisors, whose sum is σ = 272673823968. Its totient is φ = 14502850560.

The previous prime is 66344725439. The next prime is 66344725457. The reversal of 66344725440 is 4452744366.

66344725440 is a `hidden beast` number, since 6 + 6 + 34 + 4 + 72 + 544 + 0 = 666.

66344725440 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (504).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 10661530 + ... + 10667750.

It is an arithmetic number, because the mean of its divisors is an integer number (541019492).

Almost surely, 2^66344725440 is an apocalyptic number.

66344725440 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66344725440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (136336911984).

66344725440 is an abundant number, since it is smaller than the sum of its proper divisors (206329098528).

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

66344725440 is a wasteful number, since it uses less digits than its factorization.

66344725440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6297 (or 6261 counting only the distinct ones).

The product of its (nonzero) digits is 1935360, while the sum is 45.

The spelling of 66344725440 in words is "sixty-six billion, three hundred forty-four million, seven hundred twenty-five thousand, four hundred forty".