20555011555 has 16 divisors (see below), whose sum is σ = 26937537984. Its totient is φ = 14965292160.

The previous prime is 20555011549. The next prime is 20555011601. The reversal of 20555011555 is 55511055502.

It is not a de Polignac number, because 20555011555 - 2⁵ = 20555011523 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20555011555.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2222364 + ... + 2231593.

It is an arithmetic number, because the mean of its divisors is an integer number (1683596124).

Almost surely, 2^20555011555 is an apocalyptic number.

20555011555 is a deficient number, since it is larger than the sum of its proper divisors (6382526429).

20555011555 is a wasteful number, since it uses less digits than its factorization.

20555011555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4454046.

The product of its (nonzero) digits is 31250, while the sum is 34.

The spelling of 20555011555 in words is "twenty billion, five hundred fifty-five million, eleven thousand, five hundred fifty-five".