28919530 has 16 divisors (see below), whose sum is σ = 52715520. Its totient is φ = 11421072.

The previous prime is 28919509. The next prime is 28919531. The reversal of 28919530 is 3591982.

It is a self number, because there is not a number n which added to its sum of digits gives 28919530.

It is not an unprimeable number, because it can be changed into a prime (28919531) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17514 + ... + 19093.

It is an arithmetic number, because the mean of its divisors is an integer number (3294720).

Almost surely, 2^28919530 is an apocalyptic number.

28919530 is a deficient number, since it is larger than the sum of its proper divisors (23795990).

28919530 is a wasteful number, since it uses less digits than its factorization.

28919530 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36693.

The product of its (nonzero) digits is 19440, while the sum is 37.

The square root of 28919530 is about 5377.6881650018. The cubic root of 28919530 is about 306.9472476708.

It can be divided in two parts, 2891 and 9530, that added together give a palindrome (12421).

The spelling of 28919530 in words is "twenty-eight million, nine hundred nineteen thousand, five hundred thirty".