20505342125 has 16 divisors (see below), whose sum is σ = 26135156736. Its totient is φ = 16055242000.

The previous prime is 20505342079. The next prime is 20505342131. The reversal of 20505342125 is 52124350502.

It is not a de Polignac number, because 20505342125 - 2⁶ = 20505342061 is a prime.

It is a Duffinian number.

It is a Curzon number.

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 15 ways as a sum of consecutive naturals, for example, 1739261 + ... + 1751010.

It is an arithmetic number, because the mean of its divisors is an integer number (1633447296).

Almost surely, 2^20505342125 is an apocalyptic number.

20505342125 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20505342125 is a deficient number, since it is larger than the sum of its proper divisors (5629814611).

20505342125 is an equidigital number, since it uses as much as digits as its factorization.

20505342125 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3490333 (or 3490323 counting only the distinct ones).

The product of its (nonzero) digits is 12000, while the sum is 29.

Adding to 20505342125 its reverse (52124350502), we get a palindrome (72629692627).

The spelling of 20505342125 in words is "twenty billion, five hundred five million, three hundred forty-two thousand, one hundred twenty-five".