20518944997863 has 96 divisors (see below), whose sum is σ = 29933105157120. Its totient is φ = 12496611778560.

The previous prime is 20518944997847. The next prime is 20518944997867. The reversal of 20518944997863 is 36879944981502.

It is not a de Polignac number, because 20518944997863 - 2⁴ = 20518944997847 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20518944997867) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 27105607281 + ... + 27105608037.

It is an arithmetic number, because the mean of its divisors is an integer number (311803178720).

It is a 2-persistent number, because it is pandigital, and so is 2⋅20518944997863 = 41037889995726, but 3⋅20518944997863 = 61556834993589 is not.

Almost surely, 2^{20518944997863} is an apocalyptic number.

20518944997863 is a deficient number, since it is larger than the sum of its proper divisors (9414160159257).

20518944997863 is a wasteful number, since it uses less digits than its factorization.

20518944997863 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2049 (or 2036 counting only the distinct ones).

The product of its (nonzero) digits is 940584960, while the sum is 75.

The spelling of 20518944997863 in words is "twenty trillion, five hundred eighteen billion, nine hundred forty-four million, nine hundred ninety-seven thousand, eight hundred sixty-three".