21084041425 has 6 divisors (see below), whose sum is σ = 26144211398. Its totient is φ = 16867233120.

The previous prime is 21084041423. The next prime is 21084041431. The reversal of 21084041425 is 52414048012.

It can be written as a sum of positive squares in 3 ways, for example, as 5228446864 + 15855594561 = 72308^2 + 125919^2 .

It is not a de Polignac number, because 21084041425 - 2¹ = 21084041423 is a prime.

It is a super-2 number, since 2×21084041425² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21084041423) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 421680804 + ... + 421680853.

Almost surely, 2^21084041425 is an apocalyptic number.

21084041425 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21084041425 is a deficient number, since it is larger than the sum of its proper divisors (5060169973).

21084041425 is an equidigital number, since it uses as much as digits as its factorization.

21084041425 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 843361667 (or 843361662 counting only the distinct ones).

The product of its (nonzero) digits is 10240, while the sum is 31.

Adding to 21084041425 its reverse (52414048012), we get a palindrome (73498089437).

The spelling of 21084041425 in words is "twenty-one billion, eighty-four million, forty-one thousand, four hundred twenty-five".