21496606217 has 2 divisors, whose sum is σ = 21496606218. Its totient is φ = 21496606216.

The previous prime is 21496606211. The next prime is 21496606237. The reversal of 21496606217 is 71260669412.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17010419776 + 4486186441 = 130424^2 + 66979^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21496606217 is a prime.

It is not a weakly prime, because it can be changed into another prime (21496606211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10748303108 + 10748303109.

It is an arithmetic number, because the mean of its divisors is an integer number (10748303109).

Almost surely, 2^21496606217 is an apocalyptic number.

It is an amenable number.

21496606217 is a deficient number, since it is larger than the sum of its proper divisors (1).

21496606217 is an equidigital number, since it uses as much as digits as its factorization.

21496606217 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 217728, while the sum is 44.

The spelling of 21496606217 in words is "twenty-one billion, four hundred ninety-six million, six hundred six thousand, two hundred seventeen".