891965 has 4 divisors (see below), whose sum is σ = 1070364. Its totient is φ = 713568.

The previous prime is 891929. The next prime is 891967. The reversal of 891965 is 569198.

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 534361 + 357604 = 731^2 + 598^2 .

It is a cyclic number.

It is not a de Polignac number, because 891965 - 2¹⁰ = 890941 is a prime.

It is a super-2 number, since 2×891965² = 1591203122450, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (891967) 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, 89192 + ... + 89201.

It is an arithmetic number, because the mean of its divisors is an integer number (267591).

2⁸⁹¹⁹⁶⁵ is an apocalyptic number.

It is an amenable number.

891965 is a deficient number, since it is larger than the sum of its proper divisors (178399).

891965 is a wasteful number, since it uses less digits than its factorization.

891965 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 178398.

The product of its digits is 19440, while the sum is 38.

The square root of 891965 is about 944.4389869123. The cubic root of 891965 is about 96.2607566547.

The spelling of 891965 in words is "eight hundred ninety-one thousand, nine hundred sixty-five".