28981697 has 2 divisors, whose sum is σ = 28981698. Its totient is φ = 28981696.

The previous prime is 28981661. The next prime is 28981709. The reversal of 28981697 is 79618982.

28981697 is nontrivially palindromic in base 15.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14776336 + 14205361 = 3844^2 + 3769^2 .

It is a cyclic number.

It is not a de Polignac number, because 28981697 - 2¹² = 28977601 is a prime.

It is not a weakly prime, because it can be changed into another prime (28981607) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14490848 + 14490849.

It is an arithmetic number, because the mean of its divisors is an integer number (14490849).

Almost surely, 2^28981697 is an apocalyptic number.

It is an amenable number.

28981697 is a deficient number, since it is larger than the sum of its proper divisors (1).

28981697 is an equidigital number, since it uses as much as digits as its factorization.

28981697 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 435456, while the sum is 50.

The square root of 28981697 is about 5383.4651480250. The cubic root of 28981697 is about 307.1670337764.

The spelling of 28981697 in words is "twenty-eight million, nine hundred eighty-one thousand, six hundred ninety-seven".