28640788 has 12 divisors (see below), whose sum is σ = 54677952. Its totient is φ = 13018520.

The previous prime is 28640779. The next prime is 28640791. The reversal of 28640788 is 88704682.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 325420 + ... + 325507.

It is an arithmetic number, because the mean of its divisors is an integer number (4556496).

Almost surely, 2^28640788 is an apocalyptic number.

It is an amenable number.

28640788 is a deficient number, since it is larger than the sum of its proper divisors (26037164).

28640788 is a wasteful number, since it uses less digits than its factorization.

28640788 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 650942 (or 650940 counting only the distinct ones).

The product of its (nonzero) digits is 172032, while the sum is 43.

The square root of 28640788 is about 5351.7088859541. The cubic root of 28640788 is about 305.9578878924.

The spelling of 28640788 in words is "twenty-eight million, six hundred forty thousand, seven hundred eighty-eight".