28303772 has 18 divisors (see below), whose sum is σ = 57618792. Its totient is φ = 12130104.

The previous prime is 28303771. The next prime is 28303801. The reversal of 28303772 is 27730382.

It is a happy number.

It is a super-2 number, since 2×28303772² = 1602207018855968, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28303771) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 72008 + ... + 72399.

It is an arithmetic number, because the mean of its divisors is an integer number (3201044).

Almost surely, 2^28303772 is an apocalyptic number.

It is an amenable number.

28303772 is an abundant number, since it is smaller than the sum of its proper divisors (29315020).

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

28303772 is a wasteful number, since it uses less digits than its factorization.

28303772 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 144425 (or 144416 counting only the distinct ones).

The product of its (nonzero) digits is 14112, while the sum is 32.

The square root of 28303772 is about 5320.1289458057. The cubic root of 28303772 is about 304.7530815324.

The spelling of 28303772 in words is "twenty-eight million, three hundred three thousand, seven hundred seventy-two".