181605556147 has 2 divisors, whose sum is σ = 181605556148. Its totient is φ = 181605556146.

The previous prime is 181605556133. The next prime is 181605556151. The reversal of 181605556147 is 741655506181.

181605556147 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 181605556147 - 2¹¹ = 181605554099 is a prime.

It is a super-2 number, since 2×181605556147² (a number of 23 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 181605556147.

It is not a weakly prime, because it can be changed into another prime (181605553147) 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, 90802778073 + 90802778074.

It is an arithmetic number, because the mean of its divisors is an integer number (90802778074).

Almost surely, 2^181605556147 is an apocalyptic number.

181605556147 is a deficient number, since it is larger than the sum of its proper divisors (1).

181605556147 is an equidigital number, since it uses as much as digits as its factorization.

181605556147 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1008000, while the sum is 49.

The spelling of 181605556147 in words is "one hundred eighty-one billion, six hundred five million, five hundred fifty-six thousand, one hundred forty-seven".