28001863 has 4 divisors (see below), whose sum is σ = 28290640. Its totient is φ = 27713088.

The previous prime is 28001837. The next prime is 28001881. The reversal of 28001863 is 36810082.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28001863 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28001063) 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, 144243 + ... + 144436.

It is an arithmetic number, because the mean of its divisors is an integer number (7072660).

Almost surely, 2^28001863 is an apocalyptic number.

28001863 is a deficient number, since it is larger than the sum of its proper divisors (288777).

28001863 is an equidigital number, since it uses as much as digits as its factorization.

28001863 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 288776.

The product of its (nonzero) digits is 2304, while the sum is 28.

The square root of 28001863 is about 5291.6786561544. The cubic root of 28001863 is about 303.6656317587.

The spelling of 28001863 in words is "twenty-eight million, one thousand, eight hundred sixty-three".