28110644981 has 2 divisors, whose sum is σ = 28110644982. Its totient is φ = 28110644980.

The previous prime is 28110644909. The next prime is 28110644987. The reversal of 28110644981 is 18944601182.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 27063540100 + 1047104881 = 164510^2 + 32359^2 .

It is a cyclic number.

It is not a de Polignac number, because 28110644981 - 2²² = 28106450677 is a prime.

It is a super-2 number, since 2×28110644981² (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 (28110644987) 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, 14055322490 + 14055322491.

It is an arithmetic number, because the mean of its divisors is an integer number (14055322491).

Almost surely, 2^28110644981 is an apocalyptic number.

It is an amenable number.

28110644981 is a deficient number, since it is larger than the sum of its proper divisors (1).

28110644981 is an equidigital number, since it uses as much as digits as its factorization.

28110644981 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 110592, while the sum is 44.

The spelling of 28110644981 in words is "twenty-eight billion, one hundred ten million, six hundred forty-four thousand, nine hundred eighty-one".