28389930 has 16 divisors (see below), whose sum is σ = 68135904. Its totient is φ = 7570640.

The previous prime is 28389929. The next prime is 28389931. The reversal of 28389930 is 3998382.

It is an interprime number because it is at equal distance from previous prime (28389929) and next prime (28389931).

It is not an unprimeable number, because it can be changed into a prime (28389931) 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 in 7 ways as a sum of consecutive naturals, for example, 473136 + ... + 473195.

It is an arithmetic number, because the mean of its divisors is an integer number (4258494).

Almost surely, 2^28389930 is an apocalyptic number.

28389930 is an abundant number, since it is smaller than the sum of its proper divisors (39745974).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28389930 is a wasteful number, since it uses less digits than its factorization.

28389930 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 946341.

The product of its (nonzero) digits is 93312, while the sum is 42.

The square root of 28389930 is about 5328.2201531093. The cubic root of 28389930 is about 305.0619958182.

The spelling of 28389930 in words is "twenty-eight million, three hundred eighty-nine thousand, nine hundred thirty".