28378100 has 36 divisors (see below), whose sum is σ = 65206764. Its totient is φ = 10682880.

The previous prime is 28378099. The next prime is 28378111. The reversal of 28378100 is 187382.

It can be written as a sum of positive squares in 6 ways, for example, as 1731856 + 26646244 = 1316^2 + 5162^2 .

It is a super-2 number, since 2×28378100² = 1610633119220000, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6647 + ... + 10046.

It is an arithmetic number, because the mean of its divisors is an integer number (1811299).

Almost surely, 2^28378100 is an apocalyptic number.

28378100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28378100 is an abundant number, since it is smaller than the sum of its proper divisors (36828664).

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

28378100 is a wasteful number, since it uses less digits than its factorization.

28378100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16724 (or 16717 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 29.

The square root of 28378100 is about 5327.1099106363. The cubic root of 28378100 is about 305.0196171204.

The spelling of 28378100 in words is "twenty-eight million, three hundred seventy-eight thousand, one hundred".