20503429 has 2 divisors, whose sum is σ = 20503430. Its totient is φ = 20503428.

The previous prime is 20503409. The next prime is 20503433. The reversal of 20503429 is 92430502.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18472804 + 2030625 = 4298^2 + 1425^2 .

It is a cyclic number.

It is not a de Polignac number, because 20503429 - 2⁵ = 20503397 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20503409) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10251714 + 10251715.

It is an arithmetic number, because the mean of its divisors is an integer number (10251715).

Almost surely, 2^20503429 is an apocalyptic number.

It is an amenable number.

20503429 is a deficient number, since it is larger than the sum of its proper divisors (1).

20503429 is an equidigital number, since it uses as much as digits as its factorization.

20503429 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2160, while the sum is 25.

The square root of 20503429 is about 4528.0712229381. The cubic root of 20503429 is about 273.7004425070.

The spelling of 20503429 in words is "twenty million, five hundred three thousand, four hundred twenty-nine".