191019040258 has 4 divisors (see below), whose sum is σ = 286528560390. Its totient is φ = 95509520128.

The previous prime is 191019040229. The next prime is 191019040259. The reversal of 191019040258 is 852040910191.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 181631949489 + 9387090769 = 426183^2 + 96887^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 191019040258.

It is not an unprimeable number, because it can be changed into a prime (191019040259) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 47754760063 + ... + 47754760066.

Almost surely, 2^191019040258 is an apocalyptic number.

191019040258 is a deficient number, since it is larger than the sum of its proper divisors (95509520132).

191019040258 is an equidigital number, since it uses as much as digits as its factorization.

191019040258 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95509520131.

The product of its (nonzero) digits is 25920, while the sum is 40.

The spelling of 191019040258 in words is "one hundred ninety-one billion, nineteen million, forty thousand, two hundred fifty-eight".