21533643023 has 2 divisors, whose sum is σ = 21533643024. Its totient is φ = 21533643022.

The previous prime is 21533642993. The next prime is 21533643127. The reversal of 21533643023 is 32034633512.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21533643023 - 2³⁰ = 20459901199 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21533642023) 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, 10766821511 + 10766821512.

It is an arithmetic number, because the mean of its divisors is an integer number (10766821512).

Almost surely, 2^21533643023 is an apocalyptic number.

21533643023 is a deficient number, since it is larger than the sum of its proper divisors (1).

21533643023 is an equidigital number, since it uses as much as digits as its factorization.

21533643023 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 38880, while the sum is 32.

The spelling of 21533643023 in words is "twenty-one billion, five hundred thirty-three million, six hundred forty-three thousand, twenty-three".