28782900 has 54 divisors (see below), whose sum is σ = 90221222. Its totient is φ = 7675200.

The previous prime is 28782889. The next prime is 28782917. The reversal of 28782900 is 928782.

It can be written as a sum of positive squares in 3 ways, for example, as 10404 + 28772496 = 102^2 + 5364^2 .

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

It is a congruent number.

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 17 ways as a sum of consecutive naturals, for example, 15091 + ... + 16890.

Almost surely, 2^28782900 is an apocalyptic number.

28782900 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28782900 is an abundant number, since it is smaller than the sum of its proper divisors (61438322).

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

28782900 is a wasteful number, since it uses less digits than its factorization.

28782900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32001 (or 31991 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 36.

The square root of 28782900 is about 5364.9697110049. The cubic root of 28782900 is about 306.4630947832.

It can be divided in two parts, 2878 and 2900, that added together give a triangular number (5778 = T₁₀₇).

The spelling of 28782900 in words is "twenty-eight million, seven hundred eighty-two thousand, nine hundred".