202091 has 4 divisors (see below), whose sum is σ = 203400. Its totient is φ = 200784.

The previous prime is 202087. The next prime is 202099. The reversal of 202091 is 190202.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 190202 = 2 ⋅95101.

It is a cyclic number.

It is not a de Polignac number, because 202091 - 2² = 202087 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (202099) 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, 386 + ... + 743.

It is an arithmetic number, because the mean of its divisors is an integer number (50850).

2²⁰²⁰⁹¹ is an apocalyptic number.

202091 is a deficient number, since it is larger than the sum of its proper divisors (1309).

202091 is a wasteful number, since it uses less digits than its factorization.

202091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1308.

The product of its (nonzero) digits is 36, while the sum is 14.

The square root of 202091 is about 449.5453258571. The cubic root of 202091 is about 58.6834526404.

Adding to 202091 its reverse (190202), we get a palindrome (392293).

The spelling of 202091 in words is "two hundred two thousand, ninety-one".