28021838 has 8 divisors (see below), whose sum is σ = 45266088. Its totient is φ = 12933144.

The previous prime is 28021837. The next prime is 28021841. The reversal of 28021838 is 83812082.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28021837) 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 in 3 ways as a sum of consecutive naturals, for example, 538856 + ... + 538907.

It is an arithmetic number, because the mean of its divisors is an integer number (5658261).

Almost surely, 2^28021838 is an apocalyptic number.

28021838 is a deficient number, since it is larger than the sum of its proper divisors (17244250).

28021838 is a wasteful number, since it uses less digits than its factorization.

28021838 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1077778.

The product of its (nonzero) digits is 6144, while the sum is 32.

The square root of 28021838 is about 5293.5657169813. The cubic root of 28021838 is about 303.7378207562.

The spelling of 28021838 in words is "twenty-eight million, twenty-one thousand, eight hundred thirty-eight".