20330781617 has 2 divisors, whose sum is σ = 20330781618. Its totient is φ = 20330781616.

The previous prime is 20330781607. The next prime is 20330781619. The reversal of 20330781617 is 71618703302.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10188076096 + 10142705521 = 100936^2 + 100711^2 .

It is a cyclic number.

It is not a de Polignac number, because 20330781617 - 2¹² = 20330777521 is a prime.

Together with 20330781619, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (20330781619) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10165390808 + 10165390809.

It is an arithmetic number, because the mean of its divisors is an integer number (10165390809).

Almost surely, 2^20330781617 is an apocalyptic number.

It is an amenable number.

20330781617 is a deficient number, since it is larger than the sum of its proper divisors (1).

20330781617 is an equidigital number, since it uses as much as digits as its factorization.

20330781617 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 42336, while the sum is 38.

The spelling of 20330781617 in words is "twenty billion, three hundred thirty million, seven hundred eighty-one thousand, six hundred seventeen".