21104340263 has 2 divisors, whose sum is σ = 21104340264. Its totient is φ = 21104340262.

The previous prime is 21104340167. The next prime is 21104340329. The reversal of 21104340263 is 36204340112.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21104340263 - 2¹⁶ = 21104274727 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21104340463) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10552170131 + 10552170132.

It is an arithmetic number, because the mean of its divisors is an integer number (10552170132).

Almost surely, 2^21104340263 is an apocalyptic number.

21104340263 is a deficient number, since it is larger than the sum of its proper divisors (1).

21104340263 is an equidigital number, since it uses as much as digits as its factorization.

21104340263 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3456, while the sum is 26.

Adding to 21104340263 its reverse (36204340112), we get a palindrome (57308680375).

The spelling of 21104340263 in words is "twenty-one billion, one hundred four million, three hundred forty thousand, two hundred sixty-three".