28739917 has 2 divisors, whose sum is σ = 28739918. Its totient is φ = 28739916.

The previous prime is 28739891. The next prime is 28739929. The reversal of 28739917 is 71993782.

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., 28419561 + 320356 = 5331^2 + 566^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28739917 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28739017) 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, 14369958 + 14369959.

It is an arithmetic number, because the mean of its divisors is an integer number (14369959).

Almost surely, 2^28739917 is an apocalyptic number.

It is an amenable number.

28739917 is a deficient number, since it is larger than the sum of its proper divisors (1).

28739917 is an equidigital number, since it uses as much as digits as its factorization.

28739917 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 190512, while the sum is 46.

The square root of 28739917 is about 5360.9623203302. The cubic root of 28739917 is about 306.3104663614.

It can be divided in two parts, 287 and 39917, that added together give a palindrome (40204).

The spelling of 28739917 in words is "twenty-eight million, seven hundred thirty-nine thousand, nine hundred seventeen".