28320737 has 2 divisors, whose sum is σ = 28320738. Its totient is φ = 28320736.

The previous prime is 28320731. The next prime is 28320749. The reversal of 28320737 is 73702382.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18309841 + 10010896 = 4279^2 + 3164^2 .

It is a cyclic number.

It is not a de Polignac number, because 28320737 - 2¹² = 28316641 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (28320731) 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, 14160368 + 14160369.

It is an arithmetic number, because the mean of its divisors is an integer number (14160369).

Almost surely, 2^28320737 is an apocalyptic number.

It is an amenable number.

28320737 is a deficient number, since it is larger than the sum of its proper divisors (1).

28320737 is an equidigital number, since it uses as much as digits as its factorization.

28320737 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 14112, while the sum is 32.

The square root of 28320737 is about 5321.7231231999. The cubic root of 28320737 is about 304.8139580285.

The spelling of 28320737 in words is "twenty-eight million, three hundred twenty thousand, seven hundred thirty-seven".