28315821874 has 4 divisors (see below), whose sum is σ = 42473732814. Its totient is φ = 14157910936.

The previous prime is 28315821839. The next prime is 28315821881. The reversal of 28315821874 is 47812851382.

It is a happy number.

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., 25996725225 + 2319096649 = 161235^2 + 48157^2 .

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7078955467 + ... + 7078955470.

Almost surely, 2^28315821874 is an apocalyptic number.

28315821874 is a deficient number, since it is larger than the sum of its proper divisors (14157910940).

28315821874 is a wasteful number, since it uses less digits than its factorization.

28315821874 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14157910939.

The product of its digits is 860160, while the sum is 49.

The spelling of 28315821874 in words is "twenty-eight billion, three hundred fifteen million, eight hundred twenty-one thousand, eight hundred seventy-four".