21166472828485 has 8 divisors (see below), whose sum is σ = 25505160621336. Its totient is φ = 16862916111360.

The previous prime is 21166472828483. The next prime is 21166472828491. The reversal of 21166472828485 is 58482827466112.

It can be written as a sum of positive squares in 4 ways, for example, as 5540572160964 + 15625900667521 = 2353842^2 + 3952961^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21166472828485 - 2¹ = 21166472828483 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21166472828483) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8782767604 + ... + 8782770013.

It is an arithmetic number, because the mean of its divisors is an integer number (3188145077667).

Almost surely, 2^{21166472828485} is an apocalyptic number.

It is an amenable number.

21166472828485 is a deficient number, since it is larger than the sum of its proper divisors (4338687792851).

21166472828485 is a wasteful number, since it uses less digits than its factorization.

21166472828485 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17565537863.

The product of its digits is 82575360, while the sum is 64.

The spelling of 21166472828485 in words is "twenty-one trillion, one hundred sixty-six billion, four hundred seventy-two million, eight hundred twenty-eight thousand, four hundred eighty-five".