217620858811 has 2 divisors, whose sum is σ = 217620858812. Its totient is φ = 217620858810.

The previous prime is 217620858799. The next prime is 217620858823. The reversal of 217620858811 is 118858026712.

It is a happy number.

It is a balanced prime because it is at equal distance from previous prime (217620858799) and next prime (217620858823).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-217620858811 is a prime.

It is not a weakly prime, because it can be changed into another prime (217626858811) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108810429405 + 108810429406.

It is an arithmetic number, because the mean of its divisors is an integer number (108810429406).

Almost surely, 2^217620858811 is an apocalyptic number.

217620858811 is a deficient number, since it is larger than the sum of its proper divisors (1).

217620858811 is an equidigital number, since it uses as much as digits as its factorization.

217620858811 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 430080, while the sum is 49.

The spelling of 217620858811 in words is "two hundred seventeen billion, six hundred twenty million, eight hundred fifty-eight thousand, eight hundred eleven".