181356997 has 2 divisors, whose sum is σ = 181356998. Its totient is φ = 181356996.

The previous prime is 181356949. The next prime is 181357019. The reversal of 181356997 is 799653181.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 143976001 + 37380996 = 11999^2 + 6114^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-181356997 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 181356997.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (181356947) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 90678498 + 90678499.

It is an arithmetic number, because the mean of its divisors is an integer number (90678499).

Almost surely, 2^181356997 is an apocalyptic number.

It is an amenable number.

181356997 is a deficient number, since it is larger than the sum of its proper divisors (1).

181356997 is an equidigital number, since it uses as much as digits as its factorization.

181356997 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 408240, while the sum is 49.

The square root of 181356997 is about 13466.8852003721. The cubic root of 181356997 is about 566.0369367031.

The spelling of 181356997 in words is "one hundred eighty-one million, three hundred fifty-six thousand, nine hundred ninety-seven".