8397817855181 has 2 divisors, whose sum is σ = 8397817855182. Its totient is φ = 8397817855180.

The previous prime is 8397817855139. The next prime is 8397817855211. The reversal of 8397817855181 is 1815587187938.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5565022540900 + 2832795314281 = 2359030^2 + 1683091^2 .

It is a cyclic number.

It is not a de Polignac number, because 8397817855181 - 2¹⁴ = 8397817838797 is a prime.

It is a super-2 number, since 2×8397817855181² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8397817855111) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4198908927590 + 4198908927591.

It is an arithmetic number, because the mean of its divisors is an integer number (4198908927591).

Almost surely, 2^{8397817855181} is an apocalyptic number.

It is an amenable number.

8397817855181 is a deficient number, since it is larger than the sum of its proper divisors (1).

8397817855181 is an equidigital number, since it uses as much as digits as its factorization.

8397817855181 is an evil number, because the sum of its binary digits is even.

The product of its digits is 135475200, while the sum is 71.

The spelling of 8397817855181 in words is "eight trillion, three hundred ninety-seven billion, eight hundred seventeen million, eight hundred fifty-five thousand, one hundred eighty-one".