191240891 has 8 divisors (see below), whose sum is σ = 198626304. Its totient is φ = 183931560.

The previous prime is 191240887. The next prime is 191240897. The reversal of 191240891 is 198042191.

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

It is a cyclic number.

It is not a de Polignac number, because 191240891 - 2² = 191240887 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (191240897) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13871 + ... + 23976.

It is an arithmetic number, because the mean of its divisors is an integer number (24828288).

Almost surely, 2^191240891 is an apocalyptic number.

191240891 is a deficient number, since it is larger than the sum of its proper divisors (7385413).

191240891 is a wasteful number, since it uses less digits than its factorization.

191240891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38041.

The product of its (nonzero) digits is 5184, while the sum is 35.

The square root of 191240891 is about 13828.9873454277. The cubic root of 191240891 is about 576.1385290442.

The spelling of 191240891 in words is "one hundred ninety-one million, two hundred forty thousand, eight hundred ninety-one".