21304355071 has 4 divisors (see below), whose sum is σ = 21304647000. Its totient is φ = 21304063144.

The previous prime is 21304355047. The next prime is 21304355123. The reversal of 21304355071 is 17055340312.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 21304355071 - 2⁷ = 21304354943 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21304355771) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 71385 + ... + 218413.

It is an arithmetic number, because the mean of its divisors is an integer number (5326161750).

Almost surely, 2^21304355071 is an apocalyptic number.

21304355071 is a deficient number, since it is larger than the sum of its proper divisors (291929).

21304355071 is a wasteful number, since it uses less digits than its factorization.

21304355071 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 291928.

The product of its (nonzero) digits is 12600, while the sum is 31.

Adding to 21304355071 its reverse (17055340312), we get a palindrome (38359695383).

The spelling of 21304355071 in words is "twenty-one billion, three hundred four million, three hundred fifty-five thousand, seventy-one".