20121125205 has 16 divisors (see below), whose sum is σ = 33232310784. Its totient is φ = 10385096640.

The previous prime is 20121125201. The next prime is 20121125249. The reversal of 20121125205 is 50252112102.

It is not a de Polignac number, because 20121125205 - 2² = 20121125201 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20121125201) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 21635154 + ... + 21636083.

It is an arithmetic number, because the mean of its divisors is an integer number (2077019424).

Almost surely, 2^20121125205 is an apocalyptic number.

It is an amenable number.

20121125205 is a deficient number, since it is larger than the sum of its proper divisors (13111185579).

20121125205 is a wasteful number, since it uses less digits than its factorization.

20121125205 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43271276.

The product of its (nonzero) digits is 400, while the sum is 21.

Adding to 20121125205 its reverse (50252112102), we get a palindrome (70373237307).

The spelling of 20121125205 in words is "twenty billion, one hundred twenty-one million, one hundred twenty-five thousand, two hundred five".