28820740 has 24 divisors (see below), whose sum is σ = 65179800. Its totient is φ = 10641408.

The previous prime is 28820723. The next prime is 28820741. The reversal of 28820740 is 4702882.

It can be written as a sum of positive squares in 4 ways, for example, as 5317636 + 23503104 = 2306^2 + 4848^2 .

It is not an unprimeable number, because it can be changed into a prime (28820741) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 55165 + ... + 55684.

It is an arithmetic number, because the mean of its divisors is an integer number (2715825).

Almost surely, 2^28820740 is an apocalyptic number.

28820740 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28820740 is an abundant number, since it is smaller than the sum of its proper divisors (36359060).

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

28820740 is a wasteful number, since it uses less digits than its factorization.

28820740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110871 (or 110869 counting only the distinct ones).

The product of its (nonzero) digits is 7168, while the sum is 31.

The square root of 28820740 is about 5368.4951336478. The cubic root of 28820740 is about 306.5973351983.

The spelling of 28820740 in words is "twenty-eight million, eight hundred twenty thousand, seven hundred forty".