28660040 has 16 divisors (see below), whose sum is σ = 64485180. Its totient is φ = 11464000.

The previous prime is 28660031. The next prime is 28660043. The reversal of 28660040 is 4006682.

It can be written as a sum of positive squares in 2 ways, for example, as 28366276 + 293764 = 5326^2 + 542^2 .

It is a junction number, because it is equal to n+sod(n) for n = 28659991 and 28660009.

It is not an unprimeable number, because it can be changed into a prime (28660043) 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 3 ways as a sum of consecutive naturals, for example, 358211 + ... + 358290.

Almost surely, 2^28660040 is an apocalyptic number.

28660040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28660040 is an abundant number, since it is smaller than the sum of its proper divisors (35825140).

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

28660040 is a wasteful number, since it uses less digits than its factorization.

28660040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 716512 (or 716508 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 26.

The square root of 28660040 is about 5353.5072615996. The cubic root of 28660040 is about 306.0264262993.

The spelling of 28660040 in words is "twenty-eight million, six hundred sixty thousand, forty".