19821042 has 12 divisors (see below), whose sum is σ = 42945630. Its totient is φ = 6607008.

The previous prime is 19821041. The next prime is 19821049. The reversal of 19821042 is 24012891.

It can be written as a sum of positive squares in only one way, i.e., 16719921 + 3101121 = 4089^2 + 1761^2 .

It is a Smith number, since the sum of its digits (27) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 19820997 and 19821015.

It is not an unprimeable number, because it can be changed into a prime (19821041) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 550567 + ... + 550602.

Almost surely, 2^19821042 is an apocalyptic number.

19821042 is an abundant number, since it is smaller than the sum of its proper divisors (23124588).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

19821042 is a wasteful number, since it uses less digits than its factorization.

19821042 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1101177 (or 1101174 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 27.

The square root of 19821042 is about 4452.0828833255. The cubic root of 19821042 is about 270.6297235636.

The spelling of 19821042 in words is "nineteen million, eight hundred twenty-one thousand, forty-two".