19821065 has 48 divisors (see below), whose sum is σ = 29177280. Its totient is φ = 12794880.

The previous prime is 19821049. The next prime is 19821071. The reversal of 19821065 is 56012891.

It is not a de Polignac number, because 19821065 - 2⁴ = 19821049 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 460934 + ... + 460976.

It is an arithmetic number, because the mean of its divisors is an integer number (607860).

Almost surely, 2^19821065 is an apocalyptic number.

It is an amenable number.

19821065 is a deficient number, since it is larger than the sum of its proper divisors (9356215).

19821065 is a wasteful number, since it uses less digits than its factorization.

19821065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 122 (or 105 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 32.

The square root of 19821065 is about 4452.0854663854. The cubic root of 19821065 is about 270.6298282416.

The spelling of 19821065 in words is "nineteen million, eight hundred twenty-one thousand, sixty-five".