28311690181 has 2 divisors, whose sum is σ = 28311690182. Its totient is φ = 28311690180.

The previous prime is 28311690167. The next prime is 28311690257. The reversal of 28311690181 is 18109611382.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 27222030081 + 1089660100 = 164991^2 + 33010^2 .

It is a cyclic number.

It is not a de Polignac number, because 28311690181 - 2¹¹ = 28311688133 is a prime.

It is a super-2 number, since 2×28311690181² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28311690151) 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, 14155845090 + 14155845091.

It is an arithmetic number, because the mean of its divisors is an integer number (14155845091).

Almost surely, 2^28311690181 is an apocalyptic number.

It is an amenable number.

28311690181 is a deficient number, since it is larger than the sum of its proper divisors (1).

28311690181 is an equidigital number, since it uses as much as digits as its factorization.

28311690181 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 20736, while the sum is 40.

The spelling of 28311690181 in words is "twenty-eight billion, three hundred eleven million, six hundred ninety thousand, one hundred eighty-one".