28778064 has 80 divisors (see below), whose sum is σ = 87077760. Its totient is φ = 8017920.

The previous prime is 28778047. The next prime is 28778111. The reversal of 28778064 is 46087782.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (42).

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 15 ways as a sum of consecutive naturals, for example, 12732 + ... + 14820.

It is an arithmetic number, because the mean of its divisors is an integer number (1088472).

Almost surely, 2^28778064 is an apocalyptic number.

28778064 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 28778064, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (43538880).

28778064 is an abundant number, since it is smaller than the sum of its proper divisors (58299696).

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

28778064 is a wasteful number, since it uses less digits than its factorization.

28778064 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2148 (or 2142 counting only the distinct ones).

The product of its (nonzero) digits is 150528, while the sum is 42.

The square root of 28778064 is about 5364.5189905526. The cubic root of 28778064 is about 306.4459302105.

The spelling of 28778064 in words is "twenty-eight million, seven hundred seventy-eight thousand, sixty-four".