28768720 has 40 divisors (see below), whose sum is σ = 68450976. Its totient is φ = 11238528.

The previous prime is 28768687. The next prime is 28768799. The reversal of 28768720 is 2786782.

It is a tau number, because it is divible by the number of its divisors (40).

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 742 + ... + 7621.

Almost surely, 2^28768720 is an apocalyptic number.

28768720 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28768720 is an abundant number, since it is smaller than the sum of its proper divisors (39682256).

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

28768720 is a wasteful number, since it uses less digits than its factorization.

28768720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8419 (or 8413 counting only the distinct ones).

The product of its (nonzero) digits is 75264, while the sum is 40.

The square root of 28768720 is about 5363.6480123140. The cubic root of 28768720 is about 306.4127597983.

The spelling of 28768720 in words is "twenty-eight million, seven hundred sixty-eight thousand, seven hundred twenty".