28891069 has 2 divisors, whose sum is σ = 28891070. Its totient is φ = 28891068.

The previous prime is 28891021. The next prime is 28891073. The reversal of 28891069 is 96019882.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 24108100 + 4782969 = 4910^2 + 2187^2 .

It is a cyclic number.

It is not a de Polignac number, because 28891069 - 2⁷ = 28890941 is a prime.

It is a super-2 number, since 2×28891069² = 1669387735925522, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28891099) 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, 14445534 + 14445535.

It is an arithmetic number, because the mean of its divisors is an integer number (14445535).

Almost surely, 2^28891069 is an apocalyptic number.

It is an amenable number.

28891069 is a deficient number, since it is larger than the sum of its proper divisors (1).

28891069 is an equidigital number, since it uses as much as digits as its factorization.

28891069 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 62208, while the sum is 43.

The square root of 28891069 is about 5375.0413021669. The cubic root of 28891069 is about 306.8465211258.

The spelling of 28891069 in words is "twenty-eight million, eight hundred ninety-one thousand, sixty-nine".