191931479808 has 144 divisors (see below), whose sum is σ = 539433511680. Its totient is φ = 60414861312.

The previous prime is 191931479801. The next prime is 191931479863. The reversal of 191931479808 is 808974139191.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (191931479801) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4546285 + ... + 4588307.

Almost surely, 2^191931479808 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 191931479808, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (269716755840).

191931479808 is an abundant number, since it is smaller than the sum of its proper divisors (347502031872).

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

191931479808 is a wasteful number, since it uses less digits than its factorization.

191931479808 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42374 (or 42360 counting only the distinct ones).

The product of its (nonzero) digits is 3919104, while the sum is 60.

The spelling of 191931479808 in words is "one hundred ninety-one billion, nine hundred thirty-one million, four hundred seventy-nine thousand, eight hundred eight".