21351642516341 has 2 divisors, whose sum is σ = 21351642516342. Its totient is φ = 21351642516340.

The previous prime is 21351642516293. The next prime is 21351642516343. The reversal of 21351642516341 is 14361524615312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21131066697316 + 220575819025 = 4596854^2 + 469655^2 .

It is a cyclic number.

It is not a de Polignac number, because 21351642516341 - 2¹⁰ = 21351642515317 is a prime.

Together with 21351642516343, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 21351642516292 and 21351642516301.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21351642516343) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10675821258170 + 10675821258171.

It is an arithmetic number, because the mean of its divisors is an integer number (10675821258171).

Almost surely, 2^{21351642516341} is an apocalyptic number.

It is an amenable number.

21351642516341 is a deficient number, since it is larger than the sum of its proper divisors (1).

21351642516341 is an equidigital number, since it uses as much as digits as its factorization.

21351642516341 is an evil number, because the sum of its binary digits is even.

The product of its digits is 518400, while the sum is 44.

The spelling of 21351642516341 in words is "twenty-one trillion, three hundred fifty-one billion, six hundred forty-two million, five hundred sixteen thousand, three hundred forty-one".