28861720 has 32 divisors (see below), whose sum is σ = 65124000. Its totient is φ = 11511808.

The previous prime is 28861709. The next prime is 28861727. The reversal of 28861720 is 2716882.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28861727) 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, 17157 + ... + 18763.

It is an arithmetic number, because the mean of its divisors is an integer number (2035125).

Almost surely, 2^28861720 is an apocalyptic number.

28861720 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28861720 is an abundant number, since it is smaller than the sum of its proper divisors (36262280).

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

28861720 is a wasteful number, since it uses less digits than its factorization.

28861720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2067 (or 2063 counting only the distinct ones).

The product of its (nonzero) digits is 10752, while the sum is 34.

The square root of 28861720 is about 5372.3104899103. The cubic root of 28861720 is about 306.7425825496.

The spelling of 28861720 in words is "twenty-eight million, eight hundred sixty-one thousand, seven hundred twenty".