21365560273247 has 2 divisors, whose sum is σ = 21365560273248. Its totient is φ = 21365560273246.

The previous prime is 21365560273241. The next prime is 21365560273249. The reversal of 21365560273247 is 74237206556312.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21365560273247 - 2²⁶ = 21365493164383 is a prime.

Together with 21365560273249, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21365560273241) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10682780136623 + 10682780136624.

It is an arithmetic number, because the mean of its divisors is an integer number (10682780136624).

Almost surely, 2^{21365560273247} is an apocalyptic number.

21365560273247 is a deficient number, since it is larger than the sum of its proper divisors (1).

21365560273247 is an equidigital number, since it uses as much as digits as its factorization.

21365560273247 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12700800, while the sum is 53.

The spelling of 21365560273247 in words is "twenty-one trillion, three hundred sixty-five billion, five hundred sixty million, two hundred seventy-three thousand, two hundred forty-seven".