191506138 has 8 divisors (see below), whose sum is σ = 289326240. Its totient is φ = 95064060.

The previous prime is 191506129. The next prime is 191506157. The reversal of 191506138 is 831605191.

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 344158 + ... + 344713.

It is an arithmetic number, because the mean of its divisors is an integer number (36165780).

Almost surely, 2^191506138 is an apocalyptic number.

191506138 is a deficient number, since it is larger than the sum of its proper divisors (97820102).

191506138 is a wasteful number, since it uses less digits than its factorization.

191506138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 689012.

The product of its (nonzero) digits is 6480, while the sum is 34.

The square root of 191506138 is about 13838.5742762757. The cubic root of 191506138 is about 576.4047699054.

The spelling of 191506138 in words is "one hundred ninety-one million, five hundred six thousand, one hundred thirty-eight".