21346305647 has 2 divisors, whose sum is σ = 21346305648. Its totient is φ = 21346305646.

The previous prime is 21346305637. The next prime is 21346305653. The reversal of 21346305647 is 74650364312.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21346305647 - 2⁶ = 21346305583 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21346305637) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10673152823 + 10673152824.

It is an arithmetic number, because the mean of its divisors is an integer number (10673152824).

Almost surely, 2^21346305647 is an apocalyptic number.

21346305647 is a deficient number, since it is larger than the sum of its proper divisors (1).

21346305647 is an equidigital number, since it uses as much as digits as its factorization.

21346305647 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 362880, while the sum is 41.

Adding to 21346305647 its reverse (74650364312), we get a palindrome (95996669959).

The spelling of 21346305647 in words is "twenty-one billion, three hundred forty-six million, three hundred five thousand, six hundred forty-seven".