21314247317 has 4 divisors (see below), whose sum is σ = 23251906176. Its totient is φ = 19376588460.

The previous prime is 21314247293. The next prime is 21314247323. The reversal of 21314247317 is 71374241312.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21314247317 - 2⁸ = 21314247061 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 (21314247817) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 968829413 + ... + 968829434.

It is an arithmetic number, because the mean of its divisors is an integer number (5812976544).

Almost surely, 2^21314247317 is an apocalyptic number.

It is an amenable number.

21314247317 is a deficient number, since it is larger than the sum of its proper divisors (1937658859).

21314247317 is a wasteful number, since it uses less digits than its factorization.

21314247317 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1937658858.

The product of its digits is 28224, while the sum is 35.

Adding to 21314247317 its reverse (71374241312), we get a palindrome (92688488629).

The spelling of 21314247317 in words is "twenty-one billion, three hundred fourteen million, two hundred forty-seven thousand, three hundred seventeen".