21434331409 has 2 divisors, whose sum is σ = 21434331410. Its totient is φ = 21434331408.

The previous prime is 21434331407. The next prime is 21434331469. The reversal of 21434331409 is 90413343412.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15326440000 + 6107891409 = 123800^2 + 78153^2 .

It is a cyclic number.

It is not a de Polignac number, because 21434331409 - 2¹ = 21434331407 is a prime.

Together with 21434331407, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (21434331407) 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, 10717165704 + 10717165705.

It is an arithmetic number, because the mean of its divisors is an integer number (10717165705).

Almost surely, 2^21434331409 is an apocalyptic number.

It is an amenable number.

21434331409 is a deficient number, since it is larger than the sum of its proper divisors (1).

21434331409 is an equidigital number, since it uses as much as digits as its factorization.

21434331409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 31104, while the sum is 34.

The spelling of 21434331409 in words is "twenty-one billion, four hundred thirty-four million, three hundred thirty-one thousand, four hundred nine".