66026255551521 has 32 divisors (see below), whose sum is σ = 93025206743040. Its totient is φ = 41540546767104.

The previous prime is 66026255551439. The next prime is 66026255551541. The reversal of 66026255551521 is 12515555262066.

It is not a de Polignac number, because 66026255551521 - 2¹⁷ = 66026255420449 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66026255551541) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 13540380 + ... + 17759346.

It is an arithmetic number, because the mean of its divisors is an integer number (2907037710720).

Almost surely, 2^{66026255551521} is an apocalyptic number.

It is an amenable number.

66026255551521 is a deficient number, since it is larger than the sum of its proper divisors (26998951191519).

66026255551521 is a wasteful number, since it uses less digits than its factorization.

66026255551521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4220045.

The product of its (nonzero) digits is 5400000, while the sum is 51.

The spelling of 66026255551521 in words is "sixty-six trillion, twenty-six billion, two hundred fifty-five million, five hundred fifty-one thousand, five hundred twenty-one".