21936316393 has 2 divisors, whose sum is σ = 21936316394. Its totient is φ = 21936316392.

The previous prime is 21936316349. The next prime is 21936316453. The reversal of 21936316393 is 39361363912.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20894124304 + 1042192089 = 144548^2 + 32283^2 .

It is a cyclic number.

It is not a de Polignac number, because 21936316393 - 2⁹ = 21936315881 is a prime.

It is not a weakly prime, because it can be changed into another prime (21936316343) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10968158196 + 10968158197.

It is an arithmetic number, because the mean of its divisors is an integer number (10968158197).

Almost surely, 2^21936316393 is an apocalyptic number.

It is an amenable number.

21936316393 is a deficient number, since it is larger than the sum of its proper divisors (1).

21936316393 is an equidigital number, since it uses as much as digits as its factorization.

21936316393 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 472392, while the sum is 46.

The spelling of 21936316393 in words is "twenty-one billion, nine hundred thirty-six million, three hundred sixteen thousand, three hundred ninety-three".