891121198 has 24 divisors (see below), whose sum is σ = 1555678656. Its totient is φ = 381226560.

The previous prime is 891121169. The next prime is 891121199.

891121198 is nontrivially palindromic in base 10.

It is a self number, because there is not a number n which added to its sum of digits gives 891121198.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (891121199) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 104190 + ... + 112417.

It is an arithmetic number, because the mean of its divisors is an integer number (64819944).

Almost surely, 2^891121198 is an apocalyptic number.

891121198 is a deficient number, since it is larger than the sum of its proper divisors (664557458).

891121198 is a wasteful number, since it uses less digits than its factorization.

891121198 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 216648 (or 216637 counting only the distinct ones).

The product of its digits is 10368, while the sum is 40.

The square root of 891121198 is about 29851.6531870515. The cubic root of 891121198 is about 962.3039274074.

The spelling of 891121198 in words is "eight hundred ninety-one million, one hundred twenty-one thousand, one hundred ninety-eight".