21984324391 has 2 divisors, whose sum is σ = 21984324392. Its totient is φ = 21984324390.

The previous prime is 21984324371. The next prime is 21984324403. The reversal of 21984324391 is 19342348912.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21984324391 - 2¹⁹ = 21983800103 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21984324311) 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, 10992162195 + 10992162196.

It is an arithmetic number, because the mean of its divisors is an integer number (10992162196).

Almost surely, 2^21984324391 is an apocalyptic number.

21984324391 is a deficient number, since it is larger than the sum of its proper divisors (1).

21984324391 is an equidigital number, since it uses as much as digits as its factorization.

21984324391 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 373248, while the sum is 46.

The spelling of 21984324391 in words is "twenty-one billion, nine hundred eighty-four million, three hundred twenty-four thousand, three hundred ninety-one".