203491 has 4 divisors (see below), whose sum is σ = 207000. Its totient is φ = 199984.

The previous prime is 203461. The next prime is 203531. The reversal of 203491 is 194302.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 194302 = 2 ⋅97151.

It is a cyclic number.

It is not a de Polignac number, because 203491 - 2⁵ = 203459 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (203431) 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, 1666 + ... + 1783.

It is an arithmetic number, because the mean of its divisors is an integer number (51750).

2²⁰³⁴⁹¹ is an apocalyptic number.

203491 is a deficient number, since it is larger than the sum of its proper divisors (3509).

203491 is an equidigital number, since it uses as much as digits as its factorization.

203491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3508.

The product of its (nonzero) digits is 216, while the sum is 19.

The square root of 203491 is about 451.0997672356. The cubic root of 203491 is about 58.8186522035.

Adding to 203491 its reverse (194302), we get a palindrome (397793).

The spelling of 203491 in words is "two hundred three thousand, four hundred ninety-one".