28815779 has 2 divisors, whose sum is σ = 28815780. Its totient is φ = 28815778.

The previous prime is 28815767. The next prime is 28815793. The reversal of 28815779 is 97751882.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28815779 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (28815079) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14407889 + 14407890.

It is an arithmetic number, because the mean of its divisors is an integer number (14407890).

Almost surely, 2^28815779 is an apocalyptic number.

28815779 is a deficient number, since it is larger than the sum of its proper divisors (1).

28815779 is an equidigital number, since it uses as much as digits as its factorization.

28815779 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 282240, while the sum is 47.

The square root of 28815779 is about 5368.0330662171. The cubic root of 28815779 is about 306.5797423507.

The spelling of 28815779 in words is "twenty-eight million, eight hundred fifteen thousand, seven hundred seventy-nine".