28719720 has 48 divisors (see below), whose sum is σ = 93340260. Its totient is φ = 7658496.

The previous prime is 28719707. The next prime is 28719731. The reversal of 28719720 is 2791782.

It can be written as a sum of positive squares in 2 ways, for example, as 27941796 + 777924 = 5286^2 + 882^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 39529 + ... + 40248.

Almost surely, 2^28719720 is an apocalyptic number.

28719720 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28719720 is an abundant number, since it is smaller than the sum of its proper divisors (64620540).

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

28719720 is a wasteful number, since it uses less digits than its factorization.

28719720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79794 (or 79787 counting only the distinct ones).

The product of its (nonzero) digits is 14112, while the sum is 36.

The square root of 28719720 is about 5359.0782789581. The cubic root of 28719720 is about 306.2386962370.

The spelling of 28719720 in words is "twenty-eight million, seven hundred nineteen thousand, seven hundred twenty".