28625784 has 64 divisors (see below), whose sum is σ = 80784000. Its totient is φ = 8373120.

The previous prime is 28625783. The next prime is 28625801. The reversal of 28625784 is 48752682.

It is a happy number.

It is a super-2 number, since 2×28625784² = 1638871019229312, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28625783) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5787 + ... + 9525.

It is an arithmetic number, because the mean of its divisors is an integer number (1262250).

Almost surely, 2^28625784 is an apocalyptic number.

28625784 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28625784, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40392000).

28625784 is an abundant number, since it is smaller than the sum of its proper divisors (52158216).

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

28625784 is a wasteful number, since it uses less digits than its factorization.

28625784 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3788 (or 3784 counting only the distinct ones).

The product of its digits is 215040, while the sum is 42.

The square root of 28625784 is about 5350.3069070849. The cubic root of 28625784 is about 305.9044513504.

It can be divided in two parts, 2862 and 5784, that added together give a triangular number (8646 = T₁₃₁).

The spelling of 28625784 in words is "twenty-eight million, six hundred twenty-five thousand, seven hundred eighty-four".