191691949680 has 1760 divisors, whose sum is σ = 910978265088. Its totient is φ = 36279705600.

The previous prime is 191691949679. The next prime is 191691949747. The reversal of 191691949680 is 86949196191.

191691949680 is a `hidden beast` number, since 1 + 9 + 1 + 69 + 1 + 9 + 496 + 80 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

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 in 351 ways as a sum of consecutive naturals, for example, 6183611265 + ... + 6183611295.

Almost surely, 2^191691949680 is an apocalyptic number.

191691949680 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 191691949680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (455489132544).

191691949680 is an abundant number, since it is smaller than the sum of its proper divisors (719286315408).

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

191691949680 is a wasteful number, since it uses less digits than its factorization.

191691949680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 109 (or 76 counting only the distinct ones).

The product of its (nonzero) digits is 7558272, while the sum is 63.

The spelling of 191691949680 in words is "one hundred ninety-one billion, six hundred ninety-one million, nine hundred forty-nine thousand, six hundred eighty".