20505505125 has 32 divisors (see below), whose sum is σ = 38995617024. Its totient is φ = 9373944000.

The previous prime is 20505505093. The next prime is 20505505133. The reversal of 20505505125 is 52150550502.

It is not a de Polignac number, because 20505505125 - 2⁵ = 20505505093 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 20505505092 and 20505505101.

It is a congruent number.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 3903186 + ... + 3908435.

It is an arithmetic number, because the mean of its divisors is an integer number (1218613032).

Almost surely, 2^20505505125 is an apocalyptic number.

20505505125 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20505505125 is a deficient number, since it is larger than the sum of its proper divisors (18490111899).

20505505125 is an equidigital number, since it uses as much as digits as its factorization.

20505505125 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7811646 (or 7811636 counting only the distinct ones).

The product of its (nonzero) digits is 12500, while the sum is 30.

The spelling of 20505505125 in words is "twenty billion, five hundred five million, five hundred five thousand, one hundred twenty-five".