891961 has 4 divisors (see below), whose sum is σ = 1019392. Its totient is φ = 764532.

The previous prime is 891929. The next prime is 891967. The reversal of 891961 is 169198.

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 891961 - 2⁵ = 891929 is a prime.

It is a Duffinian number.

891961 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (891967) by changing a digit.

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, 63705 + ... + 63718.

It is an arithmetic number, because the mean of its divisors is an integer number (254848).

2⁸⁹¹⁹⁶¹ is an apocalyptic number.

It is an amenable number.

891961 is a deficient number, since it is larger than the sum of its proper divisors (127431).

891961 is a wasteful number, since it uses less digits than its factorization.

891961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 127430.

The product of its digits is 3888, while the sum is 34.

The square root of 891961 is about 944.4368692507. The cubic root of 891961 is about 96.2606127613.

The spelling of 891961 in words is "eight hundred ninety-one thousand, nine hundred sixty-one".