28144786 has 4 divisors (see below), whose sum is σ = 42217182. Its totient is φ = 14072392.

The previous prime is 28144783. The next prime is 28144789. The reversal of 28144786 is 68744182.

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

It is an interprime number because it is at equal distance from previous prime (28144783) and next prime (28144789).

It can be written as a sum of positive squares in only one way, i.e., 21483225 + 6661561 = 4635^2 + 2581^2 .

It is not an unprimeable number, because it can be changed into a prime (28144783) 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, 7036195 + ... + 7036198.

Almost surely, 2^28144786 is an apocalyptic number.

28144786 is a deficient number, since it is larger than the sum of its proper divisors (14072396).

28144786 is a wasteful number, since it uses less digits than its factorization.

28144786 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14072395.

The product of its digits is 86016, while the sum is 40.

The square root of 28144786 is about 5305.1659728985. The cubic root of 28144786 is about 304.1813971057.

The spelling of 28144786 in words is "twenty-eight million, one hundred forty-four thousand, seven hundred eighty-six".