181121328251 has 2 divisors, whose sum is σ = 181121328252. Its totient is φ = 181121328250.

The previous prime is 181121328197. The next prime is 181121328287. The reversal of 181121328251 is 152823121181.

181121328251 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 181121328251 - 2²² = 181117133947 is a prime.

It is not a weakly prime, because it can be changed into another prime (181121328851) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 90560664125 + 90560664126.

It is an arithmetic number, because the mean of its divisors is an integer number (90560664126).

Almost surely, 2^181121328251 is an apocalyptic number.

181121328251 is a deficient number, since it is larger than the sum of its proper divisors (1).

181121328251 is an equidigital number, since it uses as much as digits as its factorization.

181121328251 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7680, while the sum is 35.

The spelling of 181121328251 in words is "one hundred eighty-one billion, one hundred twenty-one million, three hundred twenty-eight thousand, two hundred fifty-one".