891998 has 8 divisors (see below), whose sum is σ = 1342008. Its totient is φ = 444664.

The previous prime is 891997. The next prime is 892019. The reversal of 891998 is 899198.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 891998.

It is not an unprimeable number, because it can be changed into a prime (891991) 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, 965 + ... + 1647.

It is an arithmetic number, because the mean of its divisors is an integer number (167751).

2⁸⁹¹⁹⁹⁸ is an apocalyptic number.

891998 is a deficient number, since it is larger than the sum of its proper divisors (450010).

891998 is a wasteful number, since it uses less digits than its factorization.

891998 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1338.

The product of its digits is 46656, while the sum is 44.

The square root of 891998 is about 944.4564574399. The cubic root of 891998 is about 96.2619437587.

The spelling of 891998 in words is "eight hundred ninety-one thousand, nine hundred ninety-eight".