19821025 has 24 divisors (see below), whose sum is σ = 28283904. Its totient is φ = 13497600.

The previous prime is 19821013. The next prime is 19821041. The reversal of 19821025 is 52012891.

It is not a de Polignac number, because 19821025 - 2⁹ = 19820513 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 19820984 and 19821002.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 33129 + ... + 33721.

It is an arithmetic number, because the mean of its divisors is an integer number (1178496).

Almost surely, 2^19821025 is an apocalyptic number.

It is an amenable number.

19821025 is a deficient number, since it is larger than the sum of its proper divisors (8462879).

19821025 is a wasteful number, since it uses less digits than its factorization.

19821025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 801 (or 796 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 28.

The square root of 19821025 is about 4452.0809741064. The cubic root of 19821025 is about 270.6296461928.

The spelling of 19821025 in words is "nineteen million, eight hundred twenty-one thousand, twenty-five".