66001325653521 has 64 divisors (see below), whose sum is σ = 101141913600000. Its totient is φ = 42512130213696.

The previous prime is 66001325653519. The next prime is 66001325653541. The reversal of 66001325653521 is 12535652310066.

66001325653521 is a `hidden beast` number, since 6 + 6 + 0 + 0 + 1 + 32 + 565 + 3 + 52 + 1 = 666.

It is not a de Polignac number, because 66001325653521 - 2¹ = 66001325653519 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66001325653541) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 604358680 + ... + 604467878.

It is an arithmetic number, because the mean of its divisors is an integer number (1580342400000).

Almost surely, 2^{66001325653521} is an apocalyptic number.

It is an amenable number.

66001325653521 is a deficient number, since it is larger than the sum of its proper divisors (35140587946479).

66001325653521 is a wasteful number, since it uses less digits than its factorization.

66001325653521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 115363 (or 115357 counting only the distinct ones).

The product of its (nonzero) digits is 972000, while the sum is 45.

Adding to 66001325653521 its reverse (12535652310066), we get a palindrome (78536977963587).

The spelling of 66001325653521 in words is "sixty-six trillion, one billion, three hundred twenty-five million, six hundred fifty-three thousand, five hundred twenty-one".