203891 has 4 divisors (see below), whose sum is σ = 207792. Its totient is φ = 199992.

The previous prime is 203873. The next prime is 203897. The reversal of 203891 is 198302.

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

It is a cyclic number.

It is not a de Polignac number, because 203891 - 2¹⁴ = 187507 is a prime.

It is a Duffinian number.

It is a zygodrome in base 2.

It is not an unprimeable number, because it can be changed into a prime (203897) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1871 + ... + 1976.

It is an arithmetic number, because the mean of its divisors is an integer number (51948).

2²⁰³⁸⁹¹ is an apocalyptic number.

203891 is a deficient number, since it is larger than the sum of its proper divisors (3901).

203891 is an equidigital number, since it uses as much as digits as its factorization.

203891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3900.

The product of its (nonzero) digits is 432, while the sum is 23.

The square root of 203891 is about 451.5429104747. The cubic root of 203891 is about 58.8571667026.

The spelling of 203891 in words is "two hundred three thousand, eight hundred ninety-one".