191938609920 has 72 divisors (see below), whose sum is σ = 613003947696. Its totient is φ = 51183628288.

The previous prime is 191938609901. The next prime is 191938609921. The reversal of 191938609920 is 29906839191.

It is not an unprimeable number, because it can be changed into a prime (191938609921) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24988167 + ... + 24995846.

It is an arithmetic number, because the mean of its divisors is an integer number (8513943718).

Almost surely, 2^191938609920 is an apocalyptic number.

191938609920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

191938609920 is an abundant number, since it is smaller than the sum of its proper divisors (421065337776).

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

191938609920 is an equidigital number, since it uses as much as digits as its factorization.

191938609920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49984037 (or 49984023 counting only the distinct ones).

The product of its (nonzero) digits is 1889568, while the sum is 57.

The spelling of 191938609920 in words is "one hundred ninety-one billion, nine hundred thirty-eight million, six hundred nine thousand, nine hundred twenty".