20381854818447 has 24 divisors (see below), whose sum is σ = 29625341709600. Its totient is φ = 13502619014400.

The previous prime is 20381854818439. The next prime is 20381854818467. The reversal of 20381854818447 is 74481845818302.

20381854818447 is a `hidden beast` number, since 2 + 0 + 3 + 8 + 1 + 8 + 548 + 1 + 84 + 4 + 7 = 666.

It is not a de Polignac number, because 20381854818447 - 2³ = 20381854818439 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20381854818467) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3217947 + ... + 7149747.

It is an arithmetic number, because the mean of its divisors is an integer number (1234389237900).

Almost surely, 2^{20381854818447} is an apocalyptic number.

20381854818447 is a deficient number, since it is larger than the sum of its proper divisors (9243486891153).

20381854818447 is a wasteful number, since it uses less digits than its factorization.

20381854818447 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3935423 (or 3935420 counting only the distinct ones).

The product of its (nonzero) digits is 55050240, while the sum is 63.

The spelling of 20381854818447 in words is "twenty trillion, three hundred eighty-one billion, eight hundred fifty-four million, eight hundred eighteen thousand, four hundred forty-seven".