19821113 has 4 divisors (see below), whose sum is σ = 21345828. Its totient is φ = 18296400.

The previous prime is 19821107. The next prime is 19821127. The reversal of 19821113 is 31112891.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 31112891 = 41 ⋅758851.

It can be written as a sum of positive squares in 2 ways, for example, as 1605289 + 18215824 = 1267^2 + 4268^2 .

It is a cyclic number.

It is not a de Polignac number, because 19821113 - 2⁶ = 19821049 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19821103) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 762338 + ... + 762363.

It is an arithmetic number, because the mean of its divisors is an integer number (5336457).

Almost surely, 2^19821113 is an apocalyptic number.

19821113 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

19821113 is a deficient number, since it is larger than the sum of its proper divisors (1524715).

19821113 is a wasteful number, since it uses less digits than its factorization.

19821113 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1524714.

The product of its digits is 432, while the sum is 26.

The square root of 19821113 is about 4452.0908571142. The cubic root of 19821113 is about 270.6300466997.

The spelling of 19821113 in words is "nineteen million, eight hundred twenty-one thousand, one hundred thirteen".