28717081 has 2 divisors, whose sum is σ = 28717082. Its totient is φ = 28717080.

The previous prime is 28717079. The next prime is 28717103. The reversal of 28717081 is 18071782.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 28249225 + 467856 = 5315^2 + 684^2 .

It is a cyclic number.

It is not a de Polignac number, because 28717081 - 2¹ = 28717079 is a prime.

It is a super-2 number, since 2×28717081² = 1649341482321122, which contains 22 as substring.

Together with 28717079, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (28717001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14358540 + 14358541.

It is an arithmetic number, because the mean of its divisors is an integer number (14358541).

Almost surely, 2^28717081 is an apocalyptic number.

It is an amenable number.

28717081 is a deficient number, since it is larger than the sum of its proper divisors (1).

28717081 is an equidigital number, since it uses as much as digits as its factorization.

28717081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6272, while the sum is 34.

The square root of 28717081 is about 5358.8320555882. The cubic root of 28717081 is about 306.2293160541.

The spelling of 28717081 in words is "twenty-eight million, seven hundred seventeen thousand, eighty-one".