20129125 has 8 divisors (see below), whose sum is σ = 25121304. Its totient is φ = 16103200.

The previous prime is 20129111. The next prime is 20129129. The reversal of 20129125 is 52192102.

It can be written as a sum of positive squares in 4 ways, for example, as 777924 + 19351201 = 882^2 + 4399^2 .

It is a de Polignac number, because none of the positive numbers 2^k-20129125 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20129096 and 20129105.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20129129) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 80392 + ... + 80641.

It is an arithmetic number, because the mean of its divisors is an integer number (3140163).

Almost surely, 2^20129125 is an apocalyptic number.

20129125 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20129125 is a deficient number, since it is larger than the sum of its proper divisors (4992179).

20129125 is an equidigital number, since it uses as much as digits as its factorization.

20129125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 161048 (or 161038 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 22.

The square root of 20129125 is about 4486.5493422005. The cubic root of 20129125 is about 272.0246742683.

The spelling of 20129125 in words is "twenty million, one hundred twenty-nine thousand, one hundred twenty-five".