28203540 has 24 divisors (see below), whose sum is σ = 78970080. Its totient is φ = 7520928.

The previous prime is 28203523. The next prime is 28203541. The reversal of 28203540 is 4530282.

It is a self number, because there is not a number n which added to its sum of digits gives 28203540.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28203541) 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, 234970 + ... + 235089.

It is an arithmetic number, because the mean of its divisors is an integer number (3290420).

Almost surely, 2^28203540 is an apocalyptic number.

28203540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28203540 is an abundant number, since it is smaller than the sum of its proper divisors (50766540).

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

28203540 is a wasteful number, since it uses less digits than its factorization.

28203540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 470071 (or 470069 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 24.

The square root of 28203540 is about 5310.7005187640. The cubic root of 28203540 is about 304.3929158809.

The spelling of 28203540 in words is "twenty-eight million, two hundred three thousand, five hundred forty".