21585139450313 has 2 divisors, whose sum is σ = 21585139450314. Its totient is φ = 21585139450312.

The previous prime is 21585139450279. The next prime is 21585139450327. The reversal of 21585139450313 is 31305493158512.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21575161038649 + 9978411664 = 4644907^2 + 99892^2 .

It is a cyclic number.

It is not a de Polignac number, because 21585139450313 - 2¹⁸ = 21585139188169 is a prime.

It is not a weakly prime, because it can be changed into another prime (21585139450333) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10792569725156 + 10792569725157.

It is an arithmetic number, because the mean of its divisors is an integer number (10792569725157).

Almost surely, 2^{21585139450313} is an apocalyptic number.

It is an amenable number.

21585139450313 is a deficient number, since it is larger than the sum of its proper divisors (1).

21585139450313 is an equidigital number, since it uses as much as digits as its factorization.

21585139450313 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1944000, while the sum is 50.

The spelling of 21585139450313 in words is "twenty-one trillion, five hundred eighty-five billion, one hundred thirty-nine million, four hundred fifty thousand, three hundred thirteen".