21347565671 has 2 divisors, whose sum is σ = 21347565672. Its totient is φ = 21347565670.

The previous prime is 21347565649. The next prime is 21347565677. The reversal of 21347565671 is 17656574312.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21347565671 - 2¹⁰ = 21347564647 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21347565677) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10673782835 + 10673782836.

It is an arithmetic number, because the mean of its divisors is an integer number (10673782836).

Almost surely, 2^21347565671 is an apocalyptic number.

21347565671 is a deficient number, since it is larger than the sum of its proper divisors (1).

21347565671 is an equidigital number, since it uses as much as digits as its factorization.

21347565671 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1058400, while the sum is 47.

The spelling of 21347565671 in words is "twenty-one billion, three hundred forty-seven million, five hundred sixty-five thousand, six hundred seventy-one".