291121 has 4 divisors (see below), whose sum is σ = 300544. Its totient is φ = 281700.

The previous prime is 291113. The next prime is 291143. The reversal of 291121 is 121192.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 291121 - 2³ = 291113 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 291095 and 291104.

It is not an unprimeable number, because it can be changed into a prime (291101) 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, 4665 + ... + 4726.

It is an arithmetic number, because the mean of its divisors is an integer number (75136).

2²⁹¹¹²¹ is an apocalyptic number.

It is an amenable number.

291121 is a deficient number, since it is larger than the sum of its proper divisors (9423).

291121 is an equidigital number, since it uses as much as digits as its factorization.

291121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9422.

The product of its digits is 36, while the sum is 16.

The square root of 291121 is about 539.5562991941. The cubic root of 291121 is about 66.2762373827.

The spelling of 291121 in words is "two hundred ninety-one thousand, one hundred twenty-one".