181397 has 2 divisors, whose sum is σ = 181398. Its totient is φ = 181396.

The previous prime is 181387. The next prime is 181399. The reversal of 181397 is 793181.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 130321 + 51076 = 361^2 + 226^2 .

It is an emirp because it is prime and its reverse (793181) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 181397 - 2⁸ = 181141 is a prime.

Together with 181399, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 181397.

It is not a weakly prime, because it can be changed into another prime (181399) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 90698 + 90699.

It is an arithmetic number, because the mean of its divisors is an integer number (90699).

2¹⁸¹³⁹⁷ is an apocalyptic number.

It is an amenable number.

181397 is a deficient number, since it is larger than the sum of its proper divisors (1).

181397 is an equidigital number, since it uses as much as digits as its factorization.

181397 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1512, while the sum is 29.

The square root of 181397 is about 425.9072669021. The cubic root of 181397 is about 56.6078551697.

The spelling of 181397 in words is "one hundred eighty-one thousand, three hundred ninety-seven".