20389129 has 2 divisors, whose sum is σ = 20389130. Its totient is φ = 20389128.

The previous prime is 20389111. The next prime is 20389151. The reversal of 20389129 is 92198302.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20250000 + 139129 = 4500^2 + 373^2 .

It is a cyclic number.

It is not a de Polignac number, because 20389129 - 2⁵ = 20389097 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20389094 and 20389103.

It is not a weakly prime, because it can be changed into another prime (20389169) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10194564 + 10194565.

It is an arithmetic number, because the mean of its divisors is an integer number (10194565).

Almost surely, 2^20389129 is an apocalyptic number.

It is an amenable number.

20389129 is a deficient number, since it is larger than the sum of its proper divisors (1).

20389129 is an equidigital number, since it uses as much as digits as its factorization.

20389129 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7776, while the sum is 34.

The square root of 20389129 is about 4515.4323159582. The cubic root of 20389129 is about 273.1908972670.

The spelling of 20389129 in words is "twenty million, three hundred eighty-nine thousand, one hundred twenty-nine".