20505506925 has 24 divisors (see below), whose sum is σ = 34079961600. Its totient is φ = 10879004800.

The previous prime is 20505506899. The next prime is 20505506927. The reversal of 20505506925 is 52960550502.

It is not a de Polignac number, because 20505506925 - 2⁷ = 20505506797 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20505506927) 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 23 ways as a sum of consecutive naturals, for example, 701400 + ... + 730049.

It is an arithmetic number, because the mean of its divisors is an integer number (1419998400).

Almost surely, 2^20505506925 is an apocalyptic number.

20505506925 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20505506925 is a deficient number, since it is larger than the sum of its proper divisors (13574454675).

20505506925 is a wasteful number, since it uses less digits than its factorization.

20505506925 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1431653 (or 1431648 counting only the distinct ones).

The product of its (nonzero) digits is 135000, while the sum is 39.

The spelling of 20505506925 in words is "twenty billion, five hundred five million, five hundred six thousand, nine hundred twenty-five".