20455455565 has 4 divisors (see below), whose sum is σ = 24546546684. Its totient is φ = 16364364448.

The previous prime is 20455455551. The next prime is 20455455571. The reversal of 20455455565 is 56555455402.

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

It can be written as a sum of positive squares in 2 ways, for example, as 2672166249 + 17783289316 = 51693^2 + 133354^2 .

It is a cyclic number.

It is not a de Polignac number, because 20455455565 - 2⁷ = 20455455437 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2045545552 + ... + 2045545561.

It is an arithmetic number, because the mean of its divisors is an integer number (6136636671).

Almost surely, 2^20455455565 is an apocalyptic number.

It is an amenable number.

20455455565 is a deficient number, since it is larger than the sum of its proper divisors (4091091119).

20455455565 is an equidigital number, since it uses as much as digits as its factorization.

20455455565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4091091118.

The product of its (nonzero) digits is 3000000, while the sum is 46.

The spelling of 20455455565 in words is "twenty billion, four hundred fifty-five million, four hundred fifty-five thousand, five hundred sixty-five".