891445 has 4 divisors (see below), whose sum is σ = 1069740. Its totient is φ = 713152.

The previous prime is 891439. The next prime is 891481. The reversal of 891445 is 544198.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 101124 + 790321 = 318^2 + 889^2 .

It is a cyclic number.

It is not a de Polignac number, because 891445 - 2⁹ = 890933 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 89140 + ... + 89149.

It is an arithmetic number, because the mean of its divisors is an integer number (267435).

2⁸⁹¹⁴⁴⁵ is an apocalyptic number.

It is an amenable number.

891445 is a deficient number, since it is larger than the sum of its proper divisors (178295).

891445 is a wasteful number, since it uses less digits than its factorization.

891445 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 178294.

The product of its digits is 5760, while the sum is 31.

The square root of 891445 is about 944.1636510690. The cubic root of 891445 is about 96.2420469057.

It can be divided in two parts, 891 and 445, that multiplied together give a triangular number (396495 = T₈₉₀).

The spelling of 891445 in words is "eight hundred ninety-one thousand, four hundred forty-five".