21421134225 has 18 divisors (see below), whose sum is σ = 38367631926. Its totient is φ = 11424604800.

The previous prime is 21421134209. The next prime is 21421134233. The reversal of 21421134225 is 52243112412.

21421134225 is a `hidden beast` number, since 2 + 1 + 421 + 13 + 4 + 225 = 666.

It can be written as a sum of positive squares in 3 ways, for example, as 688590081 + 20732544144 = 26241^2 + 143988^2 .

It is not a de Polignac number, because 21421134225 - 2⁴ = 21421134209 is a prime.

It is an unprimeable number.

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 17 ways as a sum of consecutive naturals, for example, 47602296 + ... + 47602745.

It is an arithmetic number, because the mean of its divisors is an integer number (2131535107).

Almost surely, 2^21421134225 is an apocalyptic number.

21421134225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21421134225 is a deficient number, since it is larger than the sum of its proper divisors (16946497701).

21421134225 is a wasteful number, since it uses less digits than its factorization.

21421134225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 95205057 (or 95205049 counting only the distinct ones).

The product of its digits is 3840, while the sum is 27.

Adding to 21421134225 its reverse (52243112412), we get a palindrome (73664246637).

The spelling of 21421134225 in words is "twenty-one billion, four hundred twenty-one million, one hundred thirty-four thousand, two hundred twenty-five".