20455547665645 has 4 divisors (see below), whose sum is σ = 24546657198780. Its totient is φ = 16364438132512.

The previous prime is 20455547665591. The next prime is 20455547665667. The reversal of 20455547665645 is 54656674555402.

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 2637541650601 + 17818006015044 = 1624051^2 + 4221138^2 .

It is a cyclic number.

It is not a de Polignac number, because 20455547665645 - 2¹⁹ = 20455547141357 is a prime.

It is a super-3 number, since 3×20455547665645³ (a number of 41 digits) contains 333 as substring.

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, 2045554766560 + ... + 2045554766569.

It is an arithmetic number, because the mean of its divisors is an integer number (6136664299695).

Almost surely, 2^{20455547665645} is an apocalyptic number.

It is an amenable number.

20455547665645 is a deficient number, since it is larger than the sum of its proper divisors (4091109533135).

20455547665645 is an equidigital number, since it uses as much as digits as its factorization.

20455547665645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4091109533134.

The product of its (nonzero) digits is 604800000, while the sum is 64.

The spelling of 20455547665645 in words is "twenty trillion, four hundred fifty-five billion, five hundred forty-seven million, six hundred sixty-five thousand, six hundred forty-five".