21840735017385 has 64 divisors (see below), whose sum is σ = 39881974210560. Its totient is φ = 11332264331520.

The previous prime is 21840735017371. The next prime is 21840735017389. The reversal of 21840735017385 is 58371053704812.

21840735017385 is a `hidden beast` number, since 2 + 1 + 8 + 40 + 7 + 350 + 173 + 85 = 666.

It is not a de Polignac number, because 21840735017385 - 2¹⁰ = 21840735016361 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21840735017389) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 43863279 + ... + 44358411.

It is an arithmetic number, because the mean of its divisors is an integer number (623155847040).

Almost surely, 2^{21840735017385} is an apocalyptic number.

It is an amenable number.

21840735017385 is a deficient number, since it is larger than the sum of its proper divisors (18041239193175).

21840735017385 is a wasteful number, since it uses less digits than its factorization.

21840735017385 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 504015 (or 504009 counting only the distinct ones).

The product of its (nonzero) digits is 5644800, while the sum is 54.

The spelling of 21840735017385 in words is "twenty-one trillion, eight hundred forty billion, seven hundred thirty-five million, seventeen thousand, three hundred eighty-five".