891139 has 4 divisors (see below), whose sum is σ = 900424. Its totient is φ = 881856.

The previous prime is 891133. The next prime is 891151. The reversal of 891139 is 931198.

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 891139 - 2¹⁹ = 366851 is a prime.

It is a Duffinian number.

891139 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 891139.

It is not an unprimeable number, because it can be changed into a prime (891133) 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, 4497 + ... + 4690.

It is an arithmetic number, because the mean of its divisors is an integer number (225106).

2⁸⁹¹¹³⁹ is an apocalyptic number.

891139 is a deficient number, since it is larger than the sum of its proper divisors (9285).

891139 is an equidigital number, since it uses as much as digits as its factorization.

891139 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9284.

The product of its digits is 1944, while the sum is 31.

The square root of 891139 is about 944.0015889817. The cubic root of 891139 is about 96.2310335372.

The spelling of 891139 in words is "eight hundred ninety-one thousand, one hundred thirty-nine".