181831457 has 2 divisors, whose sum is σ = 181831458. Its totient is φ = 181831456.

The previous prime is 181831417. The next prime is 181831471. The reversal of 181831457 is 754138181.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 179533201 + 2298256 = 13399^2 + 1516^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-181831457 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 181831457.

It is not a weakly prime, because it can be changed into another prime (181831417) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 90915728 + 90915729.

It is an arithmetic number, because the mean of its divisors is an integer number (90915729).

Almost surely, 2^181831457 is an apocalyptic number.

It is an amenable number.

181831457 is a deficient number, since it is larger than the sum of its proper divisors (1).

181831457 is an equidigital number, since it uses as much as digits as its factorization.

181831457 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 26880, while the sum is 38.

The square root of 181831457 is about 13484.4894971964. The cubic root of 181831457 is about 566.5301223873.

The spelling of 181831457 in words is "one hundred eighty-one million, eight hundred thirty-one thousand, four hundred fifty-seven".