28744720 has 40 divisors (see below), whose sum is σ = 70352640. Its totient is φ = 10892160.

The previous prime is 28744697. The next prime is 28744721. The reversal of 28744720 is 2744782.

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

It is not an unprimeable number, because it can be changed into a prime (28744721) 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, 7936 + ... + 10975.

It is an arithmetic number, because the mean of its divisors is an integer number (1758816).

Almost surely, 2^28744720 is an apocalyptic number.

28744720 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28744720 is an abundant number, since it is smaller than the sum of its proper divisors (41607920).

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

28744720 is a wasteful number, since it uses less digits than its factorization.

28744720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18943 (or 18937 counting only the distinct ones).

The product of its (nonzero) digits is 25088, while the sum is 34.

The square root of 28744720 is about 5361.4102622351. The cubic root of 28744720 is about 306.3275288929.

The spelling of 28744720 in words is "twenty-eight million, seven hundred forty-four thousand, seven hundred twenty".