21715617066127 has 2 divisors, whose sum is σ = 21715617066128. Its totient is φ = 21715617066126.

The previous prime is 21715617066113. The next prime is 21715617066151. The reversal of 21715617066127 is 72166071651712.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21715617066127 - 2⁷ = 21715617065999 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21715617066107) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10857808533063 + 10857808533064.

It is an arithmetic number, because the mean of its divisors is an integer number (10857808533064).

Almost surely, 2^{21715617066127} is an apocalyptic number.

21715617066127 is a deficient number, since it is larger than the sum of its proper divisors (1).

21715617066127 is an equidigital number, since it uses as much as digits as its factorization.

21715617066127 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1481760, while the sum is 52.

The spelling of 21715617066127 in words is "twenty-one trillion, seven hundred fifteen billion, six hundred seventeen million, sixty-six thousand, one hundred twenty-seven".