21350805239663 has 2 divisors, whose sum is σ = 21350805239664. Its totient is φ = 21350805239662.

The previous prime is 21350805239639. The next prime is 21350805239681. The reversal of 21350805239663 is 36693250805312.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21350805239663 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21350805239633) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10675402619831 + 10675402619832.

It is an arithmetic number, because the mean of its divisors is an integer number (10675402619832).

Almost surely, 2^{21350805239663} is an apocalyptic number.

21350805239663 is a deficient number, since it is larger than the sum of its proper divisors (1).

21350805239663 is an equidigital number, since it uses as much as digits as its factorization.

21350805239663 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6998400, while the sum is 53.

The spelling of 21350805239663 in words is "twenty-one trillion, three hundred fifty billion, eight hundred five million, two hundred thirty-nine thousand, six hundred sixty-three".