20518395955 has 16 divisors (see below), whose sum is σ = 25479609120. Its totient is φ = 15843405312.

The previous prime is 20518395943. The next prime is 20518396009. The reversal of 20518395955 is 55959381502.

It is a cyclic number.

It is not a de Polignac number, because 20518395955 - 2²⁵ = 20484841523 is a prime.

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 15 ways as a sum of consecutive naturals, for example, 444472 + ... + 488458.

It is an arithmetic number, because the mean of its divisors is an integer number (1592475570).

Almost surely, 2^20518395955 is an apocalyptic number.

20518395955 is a deficient number, since it is larger than the sum of its proper divisors (4961213165).

20518395955 is a wasteful number, since it uses less digits than its factorization.

20518395955 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47238.

The product of its (nonzero) digits is 2430000, while the sum is 52.

The spelling of 20518395955 in words is "twenty billion, five hundred eighteen million, three hundred ninety-five thousand, nine hundred fifty-five".