381180781 has 2 divisors, whose sum is σ = 381180782. Its totient is φ = 381180780.

The previous prime is 381180733. The next prime is 381180797. The reversal of 381180781 is 187081183.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 378652681 + 2528100 = 19459^2 + 1590^2 .

It is a cyclic number.

It is not a de Polignac number, because 381180781 - 2⁹ = 381180269 is a prime.

It is a super-2 number, since 2×381180781² = 290597575607539922, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 381180781.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (381180581) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 190590390 + 190590391.

It is an arithmetic number, because the mean of its divisors is an integer number (190590391).

Almost surely, 2^381180781 is an apocalyptic number.

It is an amenable number.

381180781 is a deficient number, since it is larger than the sum of its proper divisors (1).

381180781 is an equidigital number, since it uses as much as digits as its factorization.

381180781 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10752, while the sum is 37.

The square root of 381180781 is about 19523.8515923472. The cubic root of 381180781 is about 725.0650950668.

The spelling of 381180781 in words is "three hundred eighty-one million, one hundred eighty thousand, seven hundred eighty-one".