191285808 has 120 divisors (see below), whose sum is σ = 579462912. Its totient is φ = 54214272.

The previous prime is 191285771. The next prime is 191285821. The reversal of 191285808 is 808582191.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a self number, because there is not a number n which added to its sum of digits gives 191285808.

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 392541 + ... + 393027.

Almost surely, 2^191285808 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 191285808, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (289731456).

191285808 is an abundant number, since it is smaller than the sum of its proper divisors (388177104).

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

191285808 is a wasteful number, since it uses less digits than its factorization.

191285808 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 679 (or 666 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 42.

The square root of 191285808 is about 13830.6112663179. The cubic root of 191285808 is about 576.1836316517.

The spelling of 191285808 in words is "one hundred ninety-one million, two hundred eighty-five thousand, eight hundred eight".