20561410403 has 2 divisors, whose sum is σ = 20561410404. Its totient is φ = 20561410402.

The previous prime is 20561410369. The next prime is 20561410409. The reversal of 20561410403 is 30401416502.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20561410403 - 2¹⁸ = 20561148259 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (20561410409) 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 as a sum of consecutive naturals, namely, 10280705201 + 10280705202.

It is an arithmetic number, because the mean of its divisors is an integer number (10280705202).

Almost surely, 2^20561410403 is an apocalyptic number.

20561410403 is a deficient number, since it is larger than the sum of its proper divisors (1).

20561410403 is an equidigital number, since it uses as much as digits as its factorization.

20561410403 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2880, while the sum is 26.

Adding to 20561410403 its reverse (30401416502), we get a palindrome (50962826905).

The spelling of 20561410403 in words is "twenty billion, five hundred sixty-one million, four hundred ten thousand, four hundred three".