21242236403 has 2 divisors, whose sum is σ = 21242236404. Its totient is φ = 21242236402.

The previous prime is 21242236391. The next prime is 21242236429. The reversal of 21242236403 is 30463224212.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21242236403 - 2⁴ = 21242236387 is a prime.

It is not a weakly prime, because it can be changed into another prime (21242256403) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10621118201 + 10621118202.

It is an arithmetic number, because the mean of its divisors is an integer number (10621118202).

Almost surely, 2^21242236403 is an apocalyptic number.

21242236403 is a deficient number, since it is larger than the sum of its proper divisors (1).

21242236403 is an equidigital number, since it uses as much as digits as its factorization.

21242236403 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 13824, while the sum is 29.

The spelling of 21242236403 in words is "twenty-one billion, two hundred forty-two million, two hundred thirty-six thousand, four hundred three".