19821869145 has 48 divisors (see below), whose sum is σ = 37016288400. Its totient is φ = 9754380288.

The previous prime is 19821869107. The next prime is 19821869191. The reversal of 19821869145 is 54196812891.

It can be written as a sum of positive squares in 8 ways, for example, as 11204645904 + 8617223241 = 105852^2 + 92829^2 .

It is not a de Polignac number, because 19821869145 - 2⁸ = 19821868889 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 19821869091 and 19821869100.

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 47 ways as a sum of consecutive naturals, for example, 1778109 + ... + 1789221.

It is an arithmetic number, because the mean of its divisors is an integer number (771172675).

Almost surely, 2^19821869145 is an apocalyptic number.

19821869145 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

19821869145 is a deficient number, since it is larger than the sum of its proper divisors (17194419255).

19821869145 is a wasteful number, since it uses less digits than its factorization.

19821869145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14186 (or 14183 counting only the distinct ones).

The product of its digits is 1244160, while the sum is 54.

The spelling of 19821869145 in words is "nineteen billion, eight hundred twenty-one million, eight hundred sixty-nine thousand, one hundred forty-five".