891291 has 4 divisors (see below), whose sum is σ = 1188392. Its totient is φ = 594192.

The previous prime is 891287. The next prime is 891311. The reversal of 891291 is 192198.

891291 is nontrivially palindromic in base 2.

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

It is not a de Polignac number, because 891291 - 2² = 891287 is a prime.

It is a D-number.

It is a Duffinian number.

891291 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (891251) 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, 148546 + ... + 148551.

It is an arithmetic number, because the mean of its divisors is an integer number (297098).

2⁸⁹¹²⁹¹ is an apocalyptic number.

891291 is a deficient number, since it is larger than the sum of its proper divisors (297101).

891291 is a wasteful number, since it uses less digits than its factorization.

891291 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 297100.

The product of its digits is 1296, while the sum is 30.

The square root of 891291 is about 944.0820938880. The cubic root of 891291 is about 96.2365045451.

The spelling of 891291 in words is "eight hundred ninety-one thousand, two hundred ninety-one".