20320355555 has 32 divisors (see below), whose sum is σ = 25422807744. Its totient is φ = 15582468096.

The previous prime is 20320355521. The next prime is 20320355557. The reversal of 20320355555 is 55555302302.

It is not a de Polignac number, because 20320355555 - 2³² = 16025388259 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20320355557) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2065007 + ... + 2074823.

It is an arithmetic number, because the mean of its divisors is an integer number (794462742).

Almost surely, 2^20320355555 is an apocalyptic number.

20320355555 is a deficient number, since it is larger than the sum of its proper divisors (5102452189).

20320355555 is a wasteful number, since it uses less digits than its factorization.

20320355555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10055.

The product of its (nonzero) digits is 112500, while the sum is 35.

Adding to 20320355555 its reverse (55555302302), we get a palindrome (75875657857).

The spelling of 20320355555 in words is "twenty billion, three hundred twenty million, three hundred fifty-five thousand, five hundred fifty-five".