20105020501505 has 4 divisors (see below), whose sum is σ = 24126024601812. Its totient is φ = 16084016401200.

The previous prime is 20105020501499. The next prime is 20105020501507. The reversal of 20105020501505 is 50510502050102.

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 11361975787009 + 8743044714496 = 3370753^2 + 2956864^2 .

It is not a de Polignac number, because 20105020501505 - 2⁶ = 20105020501441 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20105020501507) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2010502050146 + ... + 2010502050155.

It is an arithmetic number, because the mean of its divisors is an integer number (6031506150453).

Almost surely, 2^{20105020501505} is an apocalyptic number.

It is an amenable number.

20105020501505 is a deficient number, since it is larger than the sum of its proper divisors (4021004100307).

20105020501505 is an equidigital number, since it uses as much as digits as its factorization.

20105020501505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4021004100306.

The product of its (nonzero) digits is 2500, while the sum is 26.

Adding to 20105020501505 its reverse (50510502050102), we get a palindrome (70615522551607).

The spelling of 20105020501505 in words is "twenty trillion, one hundred five billion, twenty million, five hundred one thousand, five hundred five".