191491436 has 6 divisors (see below), whose sum is σ = 335110020. Its totient is φ = 95745716.

The previous prime is 191491423. The next prime is 191491441. The reversal of 191491436 is 634194191.

It is a super-2 number, since 2×191491436² = 73337940122684192, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 191491436.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 23936426 + ... + 23936433.

It is an arithmetic number, because the mean of its divisors is an integer number (55851670).

Almost surely, 2^191491436 is an apocalyptic number.

It is an amenable number.

191491436 is a deficient number, since it is larger than the sum of its proper divisors (143618584).

191491436 is a wasteful number, since it uses less digits than its factorization.

191491436 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47872863 (or 47872861 counting only the distinct ones).

The product of its digits is 23328, while the sum is 38.

The square root of 191491436 is about 13838.0430697408. The cubic root of 191491436 is about 576.3900192559.

The spelling of 191491436 in words is "one hundred ninety-one million, four hundred ninety-one thousand, four hundred thirty-six".