181311797 has 2 divisors, whose sum is σ = 181311798. Its totient is φ = 181311796.

The previous prime is 181311791. The next prime is 181311847. The reversal of 181311797 is 797113181.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 95082001 + 86229796 = 9751^2 + 9286^2 .

It is an emirp because it is prime and its reverse (797113181) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 181311797 - 2⁸ = 181311541 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 181311797.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (181311791) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 90655898 + 90655899.

It is an arithmetic number, because the mean of its divisors is an integer number (90655899).

Almost surely, 2^181311797 is an apocalyptic number.

It is an amenable number.

181311797 is a deficient number, since it is larger than the sum of its proper divisors (1).

181311797 is an equidigital number, since it uses as much as digits as its factorization.

181311797 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10584, while the sum is 38.

The square root of 181311797 is about 13465.2069052057. The cubic root of 181311797 is about 565.9899079223.

The spelling of 181311797 in words is "one hundred eighty-one million, three hundred eleven thousand, seven hundred ninety-seven".