191121998 has 8 divisors (see below), whose sum is σ = 287033808. Its totient is φ = 95444064.

The previous prime is 191121991. The next prime is 191122003. The reversal of 191121998 is 899121191.

191121998 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (191121991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 56411 + ... + 59702.

It is an arithmetic number, because the mean of its divisors is an integer number (35879226).

Almost surely, 2^191121998 is an apocalyptic number.

191121998 is a deficient number, since it is larger than the sum of its proper divisors (95911810).

191121998 is a wasteful number, since it uses less digits than its factorization.

191121998 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 116938.

The product of its digits is 11664, while the sum is 41.

The square root of 191121998 is about 13824.6879892459. The cubic root of 191121998 is about 576.0191106539.

The spelling of 191121998 in words is "one hundred ninety-one million, one hundred twenty-one thousand, nine hundred ninety-eight".