21232403813 has 2 divisors, whose sum is σ = 21232403814. Its totient is φ = 21232403812.

The previous prime is 21232403807. The next prime is 21232403821. The reversal of 21232403813 is 31830423212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12126854884 + 9105548929 = 110122^2 + 95423^2 .

It is a cyclic number.

It is not a de Polignac number, because 21232403813 - 2¹⁸ = 21232141669 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21232403833) 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, 10616201906 + 10616201907.

It is an arithmetic number, because the mean of its divisors is an integer number (10616201907).

Almost surely, 2^21232403813 is an apocalyptic number.

It is an amenable number.

21232403813 is a deficient number, since it is larger than the sum of its proper divisors (1).

21232403813 is an equidigital number, since it uses as much as digits as its factorization.

21232403813 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6912, while the sum is 29.

The spelling of 21232403813 in words is "twenty-one billion, two hundred thirty-two million, four hundred three thousand, eight hundred thirteen".