20012555555 has 4 divisors (see below), whose sum is σ = 24015066672. Its totient is φ = 16010044440.

The previous prime is 20012555539. The next prime is 20012555557. The reversal of 20012555555 is 55555521002.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 20012555555 - 2⁴ = 20012555539 is a prime.

It is a super-2 number, since 2×20012555555² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20012555557) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2001255551 + ... + 2001255560.

It is an arithmetic number, because the mean of its divisors is an integer number (6003766668).

Almost surely, 2^20012555555 is an apocalyptic number.

20012555555 is a deficient number, since it is larger than the sum of its proper divisors (4002511117).

20012555555 is an equidigital number, since it uses as much as digits as its factorization.

20012555555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4002511116.

The product of its (nonzero) digits is 62500, while the sum is 35.

The spelling of 20012555555 in words is "twenty billion, twelve million, five hundred fifty-five thousand, five hundred fifty-five".