891391198 has 16 divisors (see below), whose sum is σ = 1375630704. Its totient is φ = 432889920.

The previous prime is 891391187. The next prime is 891391211. The reversal of 891391198 is 891193198.

It is a happy number.

891391198 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 33178 + ... + 53698.

It is an arithmetic number, because the mean of its divisors is an integer number (85976919).

Almost surely, 2^891391198 is an apocalyptic number.

891391198 is a deficient number, since it is larger than the sum of its proper divisors (484239506).

891391198 is a wasteful number, since it uses less digits than its factorization.

891391198 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21147.

The product of its digits is 139968, while the sum is 49.

The square root of 891391198 is about 29856.1752071494. The cubic root of 891391198 is about 962.4011067900.

The spelling of 891391198 in words is "eight hundred ninety-one million, three hundred ninety-one thousand, one hundred ninety-eight".