21307427347 has 4 divisors (see below), whose sum is σ = 21332407600. Its totient is φ = 21282447096.

The previous prime is 21307427293. The next prime is 21307427357. The reversal of 21307427347 is 74372470312.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21307427347 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21307427357) 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, 12488847 + ... + 12490552.

It is an arithmetic number, because the mean of its divisors is an integer number (5333101900).

Almost surely, 2^21307427347 is an apocalyptic number.

21307427347 is a deficient number, since it is larger than the sum of its proper divisors (24980253).

21307427347 is an equidigital number, since it uses as much as digits as its factorization.

21307427347 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24980252.

The product of its (nonzero) digits is 197568, while the sum is 40.

Adding to 21307427347 its reverse (74372470312), we get a palindrome (95679897659).

The spelling of 21307427347 in words is "twenty-one billion, three hundred seven million, four hundred twenty-seven thousand, three hundred forty-seven".