28778400 has 216 divisors, whose sum is σ = 116180064. Its totient is φ = 6566400.

The previous prime is 28778389. The next prime is 28778419. The reversal of 28778400 is 487782.

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

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 50115 + ... + 50685.

Almost surely, 2^28778400 is an apocalyptic number.

28778400 is a gapful number since it is divisible by the number (20) 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 28778400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (58090032).

28778400 is an abundant number, since it is smaller than the sum of its proper divisors (87401664).

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

28778400 is a wasteful number, since it uses less digits than its factorization.

28778400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 604 (or 588 counting only the distinct ones).

The product of its (nonzero) digits is 25088, while the sum is 36.

The square root of 28778400 is about 5364.5503073417. The cubic root of 28778400 is about 306.4471228485.

It can be divided in two parts, 287 and 78400, that added together give a palindrome (78687).

The spelling of 28778400 in words is "twenty-eight million, seven hundred seventy-eight thousand, four hundred".