20003561255511 has 8 divisors (see below), whose sum is σ = 29634905563760. Its totient is φ = 13335707503656.

The previous prime is 20003561255497. The next prime is 20003561255521. The reversal of 20003561255511 is 11555216530002.

20003561255511 is a `hidden beast` number, since 2 + 0 + 0 + 0 + 35 + 61 + 2 + 55 + 511 = 666.

It is not a de Polignac number, because 20003561255511 - 2¹¹ = 20003561253463 is a prime.

It is a super-2 number, since 2×20003561255511² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20003561255521) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 370436319520 + ... + 370436319573.

It is an arithmetic number, because the mean of its divisors is an integer number (3704363195470).

Almost surely, 2^{20003561255511} is an apocalyptic number.

20003561255511 is a deficient number, since it is larger than the sum of its proper divisors (9631344308249).

20003561255511 is an equidigital number, since it uses as much as digits as its factorization.

20003561255511 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 740872639102 (or 740872639096 counting only the distinct ones).

The product of its (nonzero) digits is 45000, while the sum is 36.

Adding to 20003561255511 its reverse (11555216530002), we get a palindrome (31558777785513).

The spelling of 20003561255511 in words is "twenty trillion, three billion, five hundred sixty-one million, two hundred fifty-five thousand, five hundred eleven".