66525242643540 has 144 divisors (see below), whose sum is σ = 209098973800080. Its totient is φ = 17099837798400.

The previous prime is 66525242643529. The next prime is 66525242643577. The reversal of 66525242643540 is 4534624252566.

66525242643540 is a `hidden beast` number, since 6 + 6 + 5 + 2 + 5 + 24 + 264 + 354 + 0 = 666.

It can be written as a sum of positive squares in 8 ways, for example, as 554232603024 + 65971010040516 = 744468^2 + 8122254^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 7465359 + ... + 13739798.

It is an arithmetic number, because the mean of its divisors is an integer number (1452076206945).

Almost surely, 2^{66525242643540} is an apocalyptic number.

66525242643540 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

66525242643540 is an abundant number, since it is smaller than the sum of its proper divisors (142573731156540).

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

66525242643540 is a wasteful number, since it uses less digits than its factorization.

66525242643540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21205802 (or 21205797 counting only the distinct ones).

The product of its (nonzero) digits is 41472000, while the sum is 54.

The spelling of 66525242643540 in words is "sixty-six trillion, five hundred twenty-five billion, two hundred forty-two million, six hundred forty-three thousand, five hundred forty".