21603343413857 has 2 divisors, whose sum is σ = 21603343413858. Its totient is φ = 21603343413856.

The previous prime is 21603343413851. The next prime is 21603343413871. The reversal of 21603343413857 is 75831434330612.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20887011393361 + 716332020496 = 4570231^2 + 846364^2 .

It is a cyclic number.

It is not a de Polignac number, because 21603343413857 - 2¹⁸ = 21603343151713 is a prime.

It is not a weakly prime, because it can be changed into another prime (21603343413851) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10801671706928 + 10801671706929.

It is an arithmetic number, because the mean of its divisors is an integer number (10801671706929).

Almost surely, 2^{21603343413857} is an apocalyptic number.

It is an amenable number.

21603343413857 is a deficient number, since it is larger than the sum of its proper divisors (1).

21603343413857 is an equidigital number, since it uses as much as digits as its factorization.

21603343413857 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4354560, while the sum is 50.

The spelling of 21603343413857 in words is "twenty-one trillion, six hundred three billion, three hundred forty-three million, four hundred thirteen thousand, eight hundred fifty-seven".