28140386 has 4 divisors (see below), whose sum is σ = 42210582. Its totient is φ = 14070192.

The previous prime is 28140383. The next prime is 28140401. The reversal of 28140386 is 68304182.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 22992025 + 5148361 = 4795^2 + 2269^2 .

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (28140383) by changing a digit.

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 as a sum of consecutive naturals, namely, 7035095 + ... + 7035098.

Almost surely, 2^28140386 is an apocalyptic number.

28140386 is a deficient number, since it is larger than the sum of its proper divisors (14070196).

28140386 is a wasteful number, since it uses less digits than its factorization.

28140386 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14070195.

The product of its (nonzero) digits is 9216, while the sum is 32.

The square root of 28140386 is about 5304.7512665534. The cubic root of 28140386 is about 304.1655449345.

The spelling of 28140386 in words is "twenty-eight million, one hundred forty thousand, three hundred eighty-six".