21432949289 has 2 divisors, whose sum is σ = 21432949290. Its totient is φ = 21432949288.

The previous prime is 21432949273. The next prime is 21432949339. The reversal of 21432949289 is 98294923412.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19408669225 + 2024280064 = 139315^2 + 44992^2 .

It is a cyclic number.

It is not a de Polignac number, because 21432949289 - 2⁴ = 21432949273 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21432949289.

It is not a weakly prime, because it can be changed into another prime (21432949789) 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, 10716474644 + 10716474645.

It is an arithmetic number, because the mean of its divisors is an integer number (10716474645).

Almost surely, 2^21432949289 is an apocalyptic number.

It is an amenable number.

21432949289 is a deficient number, since it is larger than the sum of its proper divisors (1).

21432949289 is an equidigital number, since it uses as much as digits as its factorization.

21432949289 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2239488, while the sum is 53.

The spelling of 21432949289 in words is "twenty-one billion, four hundred thirty-two million, nine hundred forty-nine thousand, two hundred eighty-nine".