21350345563 has 2 divisors, whose sum is σ = 21350345564. Its totient is φ = 21350345562.

The previous prime is 21350345561. The next prime is 21350345591. The reversal of 21350345563 is 36554305312.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21350345563 - 2¹ = 21350345561 is a prime.

Together with 21350345561, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (21350345561) 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, 10675172781 + 10675172782.

It is an arithmetic number, because the mean of its divisors is an integer number (10675172782).

Almost surely, 2^21350345563 is an apocalyptic number.

21350345563 is a deficient number, since it is larger than the sum of its proper divisors (1).

21350345563 is an equidigital number, since it uses as much as digits as its factorization.

21350345563 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 162000, while the sum is 37.

The spelling of 21350345563 in words is "twenty-one billion, three hundred fifty million, three hundred forty-five thousand, five hundred sixty-three".