191918868 has 48 divisors (see below), whose sum is σ = 474586560. Its totient is φ = 60256000.

The previous prime is 191918851. The next prime is 191918869. The reversal of 191918868 is 868819191.

It is a self number, because there is not a number n which added to its sum of digits gives 191918868.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (191918869) 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 15 ways as a sum of consecutive naturals, for example, 7543 + ... + 20993.

It is an arithmetic number, because the mean of its divisors is an integer number (9887220).

Almost surely, 2^191918868 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 191918868, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (237293280).

191918868 is an abundant number, since it is smaller than the sum of its proper divisors (282667692).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

191918868 is a wasteful number, since it uses less digits than its factorization.

191918868 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13528 (or 13526 counting only the distinct ones).

The product of its digits is 248832, while the sum is 51.

The square root of 191918868 is about 13853.4785523348. The cubic root of 191918868 is about 576.8185579301.

The spelling of 191918868 in words is "one hundred ninety-one million, nine hundred eighteen thousand, eight hundred sixty-eight".