21593794289 has 2 divisors, whose sum is σ = 21593794290. Its totient is φ = 21593794288.

The previous prime is 21593794259. The next prime is 21593794297. The reversal of 21593794289 is 98249739512.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14977598689 + 6616195600 = 122383^2 + 81340^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21593794289 is a prime.

It is not a weakly prime, because it can be changed into another prime (21593794259) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10796897144 + 10796897145.

It is an arithmetic number, because the mean of its divisors is an integer number (10796897145).

Almost surely, 2^21593794289 is an apocalyptic number.

It is an amenable number.

21593794289 is a deficient number, since it is larger than the sum of its proper divisors (1).

21593794289 is an equidigital number, since it uses as much as digits as its factorization.

21593794289 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9797760, while the sum is 59.

The spelling of 21593794289 in words is "twenty-one billion, five hundred ninety-three million, seven hundred ninety-four thousand, two hundred eighty-nine".