28665869 has 2 divisors, whose sum is σ = 28665870. Its totient is φ = 28665868.

The previous prime is 28665839. The next prime is 28665881. The reversal of 28665869 is 96856682.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19695844 + 8970025 = 4438^2 + 2995^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28665869 is a prime.

It is a super-2 number, since 2×28665869² = 1643464091050322, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28665809) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14332934 + 14332935.

It is an arithmetic number, because the mean of its divisors is an integer number (14332935).

Almost surely, 2^28665869 is an apocalyptic number.

It is an amenable number.

28665869 is a deficient number, since it is larger than the sum of its proper divisors (1).

28665869 is an equidigital number, since it uses as much as digits as its factorization.

28665869 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1244160, while the sum is 50.

The square root of 28665869 is about 5354.0516433819. The cubic root of 28665869 is about 306.0471718754.

The spelling of 28665869 in words is "twenty-eight million, six hundred sixty-five thousand, eight hundred sixty-nine".