28388386 has 16 divisors (see below), whose sum is σ = 46489464. Its totient is φ = 12921984.

The previous prime is 28388341. The next prime is 28388401. The reversal of 28388386 is 68388382.

It can be written as a sum of positive squares in 4 ways, for example, as 17065161 + 11323225 = 4131^2 + 3365^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5581 + ... + 9376.

Almost surely, 2^28388386 is an apocalyptic number.

28388386 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

28388386 is a deficient number, since it is larger than the sum of its proper divisors (18101078).

28388386 is a wasteful number, since it uses less digits than its factorization.

28388386 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15045.

The product of its digits is 442368, while the sum is 46.

The square root of 28388386 is about 5328.0752622312. The cubic root of 28388386 is about 305.0564654035.

The spelling of 28388386 in words is "twenty-eight million, three hundred eighty-eight thousand, three hundred eighty-six".