9697155781 has 2 divisors, whose sum is σ = 9697155782. Its totient is φ = 9697155780.

The previous prime is 9697155773. The next prime is 9697155817. The reversal of 9697155781 is 1875517969.

Together with next prime (9697155817) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8806133281 + 891022500 = 93841^2 + 29850^2 .

It is a cyclic number.

It is not a de Polignac number, because 9697155781 - 2³ = 9697155773 is a prime.

It is a super-2 number, since 2×9697155781² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9697150781) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4848577890 + 4848577891.

It is an arithmetic number, because the mean of its divisors is an integer number (4848577891).

Almost surely, 2^9697155781 is an apocalyptic number.

It is an amenable number.

9697155781 is a deficient number, since it is larger than the sum of its proper divisors (1).

9697155781 is an equidigital number, since it uses as much as digits as its factorization.

9697155781 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4762800, while the sum is 58.

The square root of 9697155781 is about 98474.1376250638. The cubic root of 9697155781 is about 2132.4627689419.

The spelling of 9697155781 in words is "nine billion, six hundred ninety-seven million, one hundred fifty-five thousand, seven hundred eighty-one".