21985760393 has 2 divisors, whose sum is σ = 21985760394. Its totient is φ = 21985760392.

The previous prime is 21985760369. The next prime is 21985760441. The reversal of 21985760393 is 39306758912.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14802858889 + 7182901504 = 121667^2 + 84752^2 .

It is a cyclic number.

It is not a de Polignac number, because 21985760393 - 2¹² = 21985756297 is a prime.

It is not a weakly prime, because it can be changed into another prime (21985700393) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10992880196 + 10992880197.

It is an arithmetic number, because the mean of its divisors is an integer number (10992880197).

Almost surely, 2^21985760393 is an apocalyptic number.

It is an amenable number.

21985760393 is a deficient number, since it is larger than the sum of its proper divisors (1).

21985760393 is an equidigital number, since it uses as much as digits as its factorization.

21985760393 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2449440, while the sum is 53.

The spelling of 21985760393 in words is "twenty-one billion, nine hundred eighty-five million, seven hundred sixty thousand, three hundred ninety-three".