21251330425 has 24 divisors (see below), whose sum is σ = 29872324160. Its totient is φ = 14867323200.

The previous prime is 21251330363. The next prime is 21251330473. The reversal of 21251330425 is 52403315212.

It is not a de Polignac number, because 21251330425 - 2²¹ = 21249233273 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21251330393 and 21251330402.

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 1714581 + ... + 1726930.

Almost surely, 2^21251330425 is an apocalyptic number.

21251330425 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21251330425 is a deficient number, since it is larger than the sum of its proper divisors (8620993735).

21251330425 is a wasteful number, since it uses less digits than its factorization.

21251330425 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3441553 (or 3441548 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 28.

Adding to 21251330425 its reverse (52403315212), we get a palindrome (73654645637).

The spelling of 21251330425 in words is "twenty-one billion, two hundred fifty-one million, three hundred thirty thousand, four hundred twenty-five".