90813991616197 has 2 divisors, whose sum is σ = 90813991616198. Its totient is φ = 90813991616196.

The previous prime is 90813991616177. The next prime is 90813991616203. The reversal of 90813991616197 is 79161619931809.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 74783649244516 + 16030342371681 = 8647754^2 + 4003791^2 .

It is a cyclic number.

It is not a de Polignac number, because 90813991616197 - 2⁷ = 90813991616069 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (90813991616107) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45406995808098 + 45406995808099.

It is an arithmetic number, because the mean of its divisors is an integer number (45406995808099).

Almost surely, 2^{90813991616197} is an apocalyptic number.

It is an amenable number.

90813991616197 is a deficient number, since it is larger than the sum of its proper divisors (1).

90813991616197 is an equidigital number, since it uses as much as digits as its factorization.

90813991616197 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 39680928, while the sum is 70.

The spelling of 90813991616197 in words is "ninety trillion, eight hundred thirteen billion, nine hundred ninety-one million, six hundred sixteen thousand, one hundred ninety-seven".