21147066689527 has 4 divisors (see below), whose sum is σ = 21147121481296. Its totient is φ = 21147011897760.

The previous prime is 21147066689521. The next prime is 21147066689537. The reversal of 21147066689527 is 72598666074112.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21147066689527 - 2¹⁵ = 21147066656759 is a prime.

It is a super-3 number, since 3×21147066689527³ (a number of 41 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21147066689521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (31) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 26812818 + ... + 27590239.

It is an arithmetic number, because the mean of its divisors is an integer number (5286780370324).

Almost surely, 2^{21147066689527} is an apocalyptic number.

21147066689527 is a deficient number, since it is larger than the sum of its proper divisors (54791769).

21147066689527 is an equidigital number, since it uses as much as digits as its factorization.

21147066689527 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54791768.

The product of its (nonzero) digits is 60963840, while the sum is 64.

The spelling of 21147066689527 in words is "twenty-one trillion, one hundred forty-seven billion, sixty-six million, six hundred eighty-nine thousand, five hundred twenty-seven".